I am a paid user and preordered version 21 just to support it, because this is a really great piece of software.
Now there are the problems I am facing:
I have a 10 channel card and I can't figure out how to use output format of 5.1 channels inside 10 channel container. I need all sources (up or down)mixed to 5.1 and then to use the other 4 channels for active XO and/or multiple subwoofers with different delay and EQ.
I think separating the number of channels and the size of the container on two different combo boxes would be a good idea.
Another problem I have on a different card is with creative asio, which not only swaps center/sub with surrounds, which is solvable by a check box in JRiver, but also puts some stupid pseudo channels between the surrounds and the rears, so RL and RR channels are #9 and #10 instead of #7 and #8. I can solve that with parametric EQ, but i think a cleaner solution would be a channel matrix dialog in the output device setting, so you can choose which channel goes where.
A third problem - many onboard realtek cards have 10 independent channels, grouped as 7.1+2 on two devices, all with the same clock. The first 8 channels are exposed as one card, and the other 2 as another. JRiver can't combine them. I use ASIO4ALL to do this and then I can use all 10 channels in JRiver, but I think this is unneeded workaraound, if a native solution is implemented. The same goes for cards with say analog and digital outputs (almost any card), which can play different streams simultaneously. There are scenarios where one can use them as additional channels for active XO, and/or multiple subwoofers with different delays and EQ if they can be combined. I'd say that going furhter and having the option to combine different cheap cards into a multichannel output device would be great, because cards with more than 7.1 channels are too expensive. I think i read on the forum different clocks are a problem in this case, but somehow ASIO4ALL can overcome that, so I guess JRiver can do too