Hello MB_SOFT,
I thought about something similar. I already use FFMPEG for some video related stuff, and I think it should be able to capture and "process" an RTP stream... just haven't gone into the details of how could this be implemented. I haven't played around with pipes before so it's all new to me.
Ian, I saw also the repos you linked, and I guess at the end it is going to be something similar to what MB_SOFT is doing, althought maybe without the pipes step, but it might be compensated by the fact that there is already software working that could process the RTP stuff and just produce the audio output to be used by BASS.
Thanks for the ideas!