there are some audio clients with http interfaces - I know VLC does, for one. So depending on how fancy you want to get, there's quite a lot of buttons a dedic

there are some audio clients with http interfaces - I know VLC does, for one. So depending on how fancy you want to get, there's quite a lot of buttons a dedicated app could push on an audio client to get it to do exactly what you want, just by sending some HTTP requests (although just plain command line may be fine).