Hi, > IIUC, QEMU can expose multiple sound devices to the guest too. > > I think this means that we can have a M:N relationship between > a sound device, and an audio backend, not just 1:1. It's 1:N. Sound devices have a single backend, but a backends can service multiple sound devices. > Assuming I'm right about the M:N relationship, I assume that > of multiple cards all do playback concurrently, something > will have todo mixing of the streams ? In general it is a good idea to go with 1:1 if possible. With pulseaudio this works fine. You'll have two streams to pulseaudio then, pulseaudio does the mixing, and you'll see both streams in mixer apps. OSS devices tend to not like being opened multiple times, so you have to go with 1:N if you want multiple sound devices. qemu mixes the playback streams then. Not fully sure what happens with recording, probably all sound devices see the very same stream. take care, Gerd
