If you have varying number of channels, can you make JRiver notice this when using ASIO Bridge?
JRU:
I use the softwares called Hi-Fi Cable and ASIO Bridge. They come in a package. After installation, Hi-Fi Cable works like a virtual sound card and you can choose it to be Windows default sound device. All Windows sound is then sent to it. Using the part of the package called ASIO Bridge you can then pass this sound to JRiver. This way, all Windows sounds enters JRiver. I believe you need version 19 of JRiver.
It works well, apart from my question above (I can't get JRiver to realise when the incoming sound is only stereo, so it can be up mixed with JRSS). Here's roughly how I did, taken from memory:
1. Download and install the Hi-Fi Cable/ASIO Bridge package:
http://vbaudio.jcedeveloppement.com/Download_CABLE/HiFiCableAsioBridgeSetup_v1006.zip (direct download link). You'll need ro reboot your PC in the process.
2. Open Windows sound preferences and choose "Hi-Fi cable input" as your default playback device. Use the "Configure" button to set it up, just like any other sound card (number of speakers and so on).
3. Find and open the program ASIO Bridge on your PC. Look for the text "ASIO Device: " in the black display area. Click it and choose JRiver Media Center 19.
4. Click the button "ASIO OFF". The black display area changes and JRiver will probably open if it not already is. In the JRiver display you should see "lpc", a counting timer, "Live" and "1 of 1".
5. At this point it should actually work, so try playing something on your computer.
6. If you get problems with crackling sound or audio being out of sync with video, get back to the forum...