On Fri, Jun 08, 2018 at 08:13:24PM +0200, Holger Nessen wrote: > I'am not sure which sound backend you are using. > As far as I can remember, ALSA didn't allow multiple processes to > output sound at the same time.
Depends on the hardware. If the hardware allows mixing natively, then you can get mixing with vanilla ALSA. Otherwise you need userspace mixing, previously done by esd, nowadays done by pulseaudio.