Topic: C-Media USB Driver CM106 - CM6206 (rear speakers not working)

[cooLopke]

Hello,


I recently bought an external USB sound card, however after plugging it into the pc (windows 7 32-bit), I don't get sound from the rear speakers of my 5.1 surround setup with the windows update drivers. I use a movie with 5.1 surround sound to test the sound.

I saw that it was not working so I installed the drivers from the CD, however I still had the same problem. After some googling I found this topic:

http://laserboy.org/forum/index.php/topic,212.0.html

Setting the following line into my CM106.ini fixed the problem in Windows:

SendSurroundToBackIn6ChannelMode = 0x00000000

So far so good. However the purpose I bought this tiny usb external sound card was to allow SPDIF passthrough. Current setup:

PS3 toslink connected to CM106 (SPDIF IN) ==> CM106 (output 5.1 surround speakers using the colored input jacks). If I test the sound in PS3 the rear speakers aren't working anymore. So I thought the CM106 can't do SPDIF passthrough, but if I plug in the speakers into the pc in my sound card, the rear speakers are working.

It can be 2 problems:
- The wiring in the cm106 are wrong and need to be changed.
- There is still a problem with the drivers I installed.

Anyone have any ideas? Thank you in advance!

Regards,

cooLopke

edit: started PS3 again. If I start a game I have no audio at all coming out of the speakers.

[James]

Hello cooLopke

What was the device you bought?

I have bought probably more  than 25 external USB SND8 CM6206 sound devices that all looked exactly the same and I have noticed some variations. For one thing the DC offset voltage can vary from +1.2V to +2.5V. And, more importantly some versions have the front left and right channels reversed!

So there must be PC board routing differences between variations of the same design.

The only thing I'm really concerned about is that they can play an 8 channel wave.

Since these things can be had for pretty cheap, you might consider buying another one from a different source.

James.