scrambled channel

hairy_mutley

Active Member
Don't often have a problem with the Humax reporting a channel as scrambled. The last few times that I have seen it, it has been the same scenario; copying files to USB while watching a recording.

It happened twice this morning. Both times I used the Humax OPT+ to start a copy from internal hard disk to USB hard disk. Then started watching a recording from the internal hard disk. Part way through the playback, the screen goes black and then shows the scrambled channel message. So that I could continue watching, I tried turning the Humax off (via remote), but the ongoing copy stopped it shutting down, so I forcibly power cycled it. To tidy up the aborted copy, I FTPed to remove the incomplete .ts and its sidecard. I then restarted the copy and resumed watching the programme.

Firstly, I presume there is no other way to stop a background copy, other than power cycling?
Secondly, is anyone aware of what may cause this scrambled channel problem to be associated with copying (or at least in my experience). If it is a memory corruption as has been speculated in the past, is there anything that can be done to minimise the risk of it occurring when copying and watching?

Note that my CF is set to remove the encrypted flag, but I do not automatically decrypt, doing that only during copy to external USB. Maybe if I decrypted on the Humax, so that the copy didn't have to do it, the operation would be more reliable?

Unfortunately I didn't think to check whether (after the replay showed scrambled channel) the copy was producing a good decrypted file or not... I will try to remember to check the next time it happens.
 

Black Hole

May contain traces of nut
Firstly, I presume there is no other way to stop a background copy, other than power cycling?
Not in my experience.

Unfortunately I didn't think to check whether (after the replay showed scrambled channel) the copy was producing a good decrypted file or not... I will try to remember to check the next time it happens.
It would be interesting to see if this is the case, it would narrow down the hypotheses of what is going on.

Note that my CF is set to remove the encrypted flag, but I do not automatically decrypt, doing that only during copy to external USB. Maybe if I decrypted on the Humax, so that the copy didn't have to do it, the operation would be more reliable?
You mean the Enc flag not the encrypted flag. The Enc flag means protected. Pre-decrypting (by whatever means) would speed up your USB transfers, and may make the operation more reliable, yes.
 
OP
hairy_mutley

hairy_mutley

Active Member
It would be interesting to see if this is the case, it would narrow down the hypotheses of what is going on.
I will see if I can provoke the problem again.

You mean the Enc flag not the encrypted flag. The Enc flag means protected.
I stand corrected on the terminology and will re-read your notes on the matter.

Is this problem less likely to occur for auto decrypt? If not, then it may make the timing of the lock-ups less convenient.
But, I take your point (and BH's may)and will experiment (if I can find some spare time :confused:).
 

Black Hole

May contain traces of nut
I stand corrected on the terminology and will re-read your notes on the matter.
I'm not sure what notes I might have written on this particular matter.

It's not really your fault, the problem lies with the icon Humax chose to represent a protected recording. It is misleading to call it "Enc", which for all the world sounds like it is supposed to mean "encrypted", because all the recordings are encrypted. It's just that the HiDef recordings (in particular) are protected from being decrypted on copy to USB (or shared via DLNA with a non-DTCP compliant DLNA client), and these are the ones marked "Enc".

Therefore it is only my interpretation of "Enc" as meaning "protected", you could equally read it as "encrypted and not available for decryption". The point is that the lack of an Enc flag definitely does not mean "this recording is not encrypted" (except for those running CF and auto-decrypt - in which case it probably does, unless the decryption process hasn't got around to it yet).

Once decrypted, the WebIF media browser will show a "Dec" icon against the recording, but that is a CF addition and cannot be reflected in the SUI media browser. The Dec icon definitely means "decrypted" (which only makes sense if you know that the recording had been encrypted in the first place).

It's all very tricky, and shows how careful one has to be when choosing terminology. It is compounded by the (frequently disregarded) fact that a word might mean one thing to the author, but carry an entirely different set of connotations to the reader.

As usual, a fuller explanation of abbreviations in the above can be found in my glossary, and a list of the icons is available in the wiki (links in my sig panel below).
 
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