System Flush Finally Fixes Developing Problems While Trialling CF

Maybe run 2 pvrs in parallel with the same software, firmware, etc to see if there's any difference between your repaired unit and another one?
That's an option - and one I've used before, albeit it's a bit difficult to manage in day-to-day use. For now, think I'll stick with the in-service/repaired one and just continue to monitor as I take steps to return it to its pre-CF state in a few months' time. The issues we have are infrequent though more common than before I installed CF.
 
The in-service PVR has continued to suffer from the picture freeze-then-auto-reboot issue despite being disconnected from the network for a month. Accordingly, yesterday (31 May) I flashed the v1.03.12 Humax sent me, replacing the CF (I didn't do the RMA procedure or system flush).

Recently the issue has been less frequent at switch-on, but changing channel to London Live (from, eg, BBC News, LCN 231) now often causes the issue within a couple of minutes. London Live is on the LOCAL TV (COMAX) mux at LCN 8 which differs from the other SD muxes in that it's 4-Qam (aka QPSK) rather than 64-Qam. This, I have always assumed, explains why trying to reverse play a programme recorded on London Live doesn't (and never has) worked properly.

Foolishly, I tried changing from LCN 231 to LCN 8 this evening and, sure enough, after a while the picture froze and the PVR crashed. Despite a hard power off/on, it was impossible to resume recording of Dixon of Dock Green on TPTV (LCN 82) that had been in progress (that's why it was foolish) and resume watching LCN 231 without the PVR crashing again. Stable operation was achieved after giving up on the recording.

The freeze suggests that something is causing the MPeg decoding process to crash.

As I have two spare PVRs, there are various options to move to one of these, with or without transferring across the backlog of recordings on the current one.
 
The in-service PVR has continued to suffer from the picture freeze-then-auto-reboot issue
So the CF is exonerated then. Not that most of us thought your results would be any different.
London Live is on the LOCAL TV (COMAX) mux
It's Comux not Comax.
it's 4-Qam (aka QPSK) rather than 64-Qam. This, I have always assumed, explains why trying to reverse play a programme recorded on London Live doesn't (and never has) worked properly.
It might be something to do with the Mpeg (de)coding, but it won't be anything to do with (de)modulation, seeing as there isn't any of the latter once it's hit the disk.
 
Just to check if I've understood this correctly.
The in-service PVR has continued to suffer from the picture freeze-then-auto-reboot issue despite being disconnected from the network for a month. Accordingly, yesterday (31 May) I flashed the v1.03.12 Humax sent me, replacing the CF (I didn't do the RMA procedure or system flush).

Recently the issue has been less frequent at switch-on, but changing channel to London Live (from, eg, BBC News, LCN 231) now often causes the issue within a couple of minutes. London Live is on the LOCAL TV (COMAX) mux at LCN 8 which differs from the other SD muxes in that it's 4-Qam (aka QPSK) rather than 64-Qam. This, I have always assumed, explains why trying to reverse play a programme recorded on London Live doesn't (and never has) worked properly.
So, your HDR crashes by if you switch from BBC News (LCN 231) to London Live (LCN 8) and leave it there for a while.
(I'm trying match your scenario/test.)
Can you reproduce the results consistently?
If so, then roughly how long to you leave it on BBC News (LCN 231) before switching it to London Live (LCN 8)?
How long will leaving it on London Live (LCN 8) before it crashes?
(I've not been able to reproduce your results, but I may have misunderstood the circumstances.)

Foolishly, I tried changing from LCN 231 to LCN 8 this evening and, sure enough, after a while the picture froze and the PVR crashed. Despite a hard power off/on, it was impossible to resume recording of Dixon of Dock Green on TPTV (LCN 82) that had been in progress (that's why it was foolish) and resume watching LCN 231 without the PVR crashing again. Stable operation was achieved after giving up on the recording.

The freeze suggests that something is causing the MPeg decoding process to crash.

As I have two spare PVRs, there are various options to move to one of these, with or without transferring across the backlog of recordings on the current one.

As you suspect it's a HDR & transmission combination issue, does the same freeze happen when you swap your main HDR with a spare one?
(I still think your main HDR has hardware fault, so these tests may crash only your particular in-service/main HDR.)
 
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So the CF is exonerated then. Not that most of us thought your results would be any different.
Well, I might try the RMA procedure and system flush before concluding that for myself.
It's Comux not Comax.
Of course it is - a typo in my crib sheet for manual rescanning whence I took it.
It might be something to do with the Mpeg (de)coding, but it won't be anything to do with (de)modulation, seeing as there isn't any of the latter once it's hit the disk.
Yes, you'd expect the modulation method used for conveying the bitstream in the RF domain to have no relevance, wouldn't you? If so, then there's something inherent in the transport stream that's problematic.
 
I suspect you may have a localised issue. This is what I have tried without problem.
  • HDR on for 24 hours or so, misc actions including recordings, channel surfing, live TV viewing.
  • Switched to BBC News (LCN 231) for 30 minutes before switching it to London Live (LCN 8) and left for 50 minutes.
  • No crash.
  • Then I rewind live buffer, hit record to record the live buffer (TSR).
  • It finished, HDR slow to respond (showed "Processing..." for a while trying to access media) but did not crash.
  • On review it may have been slow due to decrypt and shrink of the live buffer recording (TSR) which are the most recent items on the queue.
  • Still on London Live (LCN 8) and no crash.
  • played recording without issue (except I have to use x4 or x8 for REW/FF - I suspect maybe due to low bitrate)
  • No crash.
  • Immediate record TPTV (LCN82) for 15-20 minutes
  • Switch to BBC News (LCN 231) for 10 minutes
  • Switch to London Live (LCN 8) for 10 minutes
  • Check recordings of London Live and TPTV - they are both fine albeit on low quality/bitrate.
  • No crash.
I suspect the issue Newcoppiceman has is local. So check reception quality. Check connections. Swap main HDR with spare HDR and retest.

Edit: after reading #30 I tried leaving on BBC News for over an hour then switching to London Live without issue.
 
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The Talking Pictures thing: it happened to me on HD-FOX, and only during a specific programme.
 
So, your HDR crashes by if you switch from BBC News (LCN 231) to London Live (LCN 8) and leave it there for a while.
That's an example case but is typical as BBC News is our default viewing. I think it's what we're switching to that's the problem. I'll experiment further this week with switches to London Live and TPTV from various services.
Can you reproduce the results consistently?
Usually not but if, like last night, you do a crash-record (because a recording was underway) it seems certain you're guaranteed the problem will occur, and even a hard power off/on won't fix. Incidentally, last night's crashes didn't cause an automatic reboot (unlike when the problem occurs at switch on) - manual intervention was required.
If so, then roughly how long to you leave it on BBC News (LCN 231) before switching it to London Live (LCN 8)?
Typically an hour or so.
How long will leaving it on London Live (LCN 8) before it crashes?
If it's going to freeze/crash then it'll do so within a couple of minutes.
As you suspect it's a HDR & transmission combination issue, does the same freeze happen when you swap your main HDR with a spare one?
I'll give it a few weeks, then try the RMA procedure and system flush. If no better, I'll install one of the spares as our main PVR and see how that goes. However, as I still have a lot of recordings on the current PVR I'll rig this so it can be easily overplugged and use for replay only - rather than get into moving media across at this stage.
(I still think your main HDR has hardware fault, so these tests may crash only your particular in-service/main HDR.)
It's looking that way, isn't it?
 
  • played recording without issue (except I have to use x4 or x8 for REW/FF - I suspect maybe due to low bitrate)
Are you sure about FF? I find it's ok at all FF speeds, but the slower REW speeds cause it to freeze and you have to go to the higher REW speeds to unfreeze it.
 
...It's looking that way, isn't it?
I think so, but it's only an educated guess.
I look out for things that may crash my/the HDR and try not to do them.
Eg for me this my shortlist
  • Humax Portal - navigate a while and watch it slow down and crash.
  • youtube-dl while watching mp4 playback - occasionally causes a crash
 
Are you sure about FF? I find it's ok at all FF speeds, but the slower REW speeds cause it to freeze and you have to go to the higher REW speeds to unfreeze it.
Strictly speaking you're right. FF is generally better than REW (which will require x2, x4 or x8 to work).
But although FF x1 works, its often too blocky (on low bitrate channels) so I can't see what's going on. So I use FF x2 or x4.
 
I think so, but it's only an educated guess.
I look out for things that may crash my/the HDR and try not to do them.
Eg for me this my shortlist
  • Humax Portal - navigate a while and watch it slow down and crash.
  • youtube-dl while watching mp4 playback - occasionally causes a crash
We've only recently used a network connection (just for the CF) so only use Freeview as a source of programmes. As previously reported, I move recorded programmes into either my personal "current" or "pending" folders (then from the latter to the former) and have found that, if it's currently recording, the system will crash roughly 1-in-20 moves whereupon it will auto reboot and I can successfully do the move I wanted.
 
have found that, if it's currently recording, the system will crash roughly 1-in-20 moves
It would be interesting to know whether you can reproduce that when playing instead of recording.
It's conceivable that these operations could upset the Humax application, as you are moving its files while it's doing something else which, unless you do it using the UI, it would be unaware of and it might cause a problem.
I can't remember now whether I've had this problem or not, but it's safest not to interfere with anything media related or disk intensive while it's recording.
 
We've only recently used a network connection (just for the CF) so only use Freeview as a source of programmes. As previously reported, I move recorded programmes into either my personal "current" or "pending" folders (then from the latter to the former) and have found that, if it's currently recording, the system will crash roughly 1-in-20 moves whereupon it will auto reboot and I can successfully do the move I wanted.
Ah, yes that sounds familiar. When reorganising/moving recordings there is a roughly 1/20 chance of the HDR crashing trying to perform the move.
 
Ah, yes that sounds familiar. When reorganising/moving recordings there is a roughly 1/20 chance of the HDR crashing trying to perform the move.
I learnt quite quickly not to do any moving or deleting while the FOX was recording. Very high risk - more like 1:4 than 20.
 
I learnt quite quickly not to do any moving or deleting while the FOX was recording. Very high risk - more like 1:4 than 20.
Although I didn't mention specifically, I meant file actions whilst the HDR is not recording. Like yourself I try not to do anything taxing while it's recording.
I still think I get roughly 1/20 crashes using file actions while the HDR is idle. I've seen it whilst copying from one HDR to another (ie network shares automount) and occasionally while doing a local move. Usually using the standard Humax GUI.
 
Beginning to get some quality data on this fault now as it seems to be "hardening". I'll try the RMA process and system flush before fully exonerating the CF (and closing this thread).

If watching one of a number of services (eg London Live, Talking Pictures TV, Sky News...) the picture freezes somewhere between 45s and 70s after picture first appears; sound continues for a few seconds then system auto-reboots and cycle repeats. I'll try to make a list of affected and unaffected services (the latter includes BBC News and BBC Parliament and, I think, all the HD services). The occasional auto-rebooting at initial startup is likely related to this behaviour.

A two-PVR method of investigating further might be required, but before that I'll try a few simple things like swapping the power board and running with the lid off and applying freezer. It might even be worth undertaking bulk replacement of all the electrolytic caps. I wouldn't mind betting it's a cap that's the problem. As an aside, last week I repaired our Neff oven which had been resetting its clock to zero when the timer alarm sounded. The 680n mains dropper capacitor (not an electrolytic) had failed - I've had similar caps fail in a smoke alarm and underfloor heating controller.
 
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