Playing music from my computer with my humax

[Dr Bones]

I'm really frustrated with this issue and have tried to resolve it myself for months - but to no avail, so I hope someone out there can help...
I have a Humax Fox T2 running the Custom Firmware connected to a Dlink DSL2680 router via homeplugs. I can access internet tv (such as skyplayer) fine. Also, my PC computer (windows 7) is connected to the router wirelessly.
On my Humax Fox T2, when I select: Media > (type=)Music > (source=)Network
it sometimes shows my PC on the network (as well has showing MediaTomb). Then I can access the music and playlists on my computer and listen to music in the living room. It is lovely when that happens...
But it only shows my PC on the network occasionally. Most of the time, it shows only MediaTomb.
So most of the time, I cannot play the music that is stored on my computer when I am downstairs in the lounge...
I simply can't figure out why that happens. Is is the (crappy) TalkTalk DSL2680 wireless router that needs replacing with something better? Or is it the settings on the router that need changing (I've read something about port forwarding, which I don't understand either)? Or is there something else I am doing wrong. Help - please...

 

[Ezra Pound]

Your Humax streams music (and video) to and from it using a protocol called DLNA, for this to work both ends must be running a program that handles DLNA, on the Humax, turning on Content Share enables DLNA, on your P.C. you need another program that makes the content available, the Built-in Windows Media player will do this, by going to Library >> Media Sharing, I'm guessing that when your Humax can 'See' your P.C. files a program like Windows Media Player is making them available. The files you want to play must be in the Media player's play list