David Kastrup writes: Although it is not a native ALSA app (due mainly to me not having the time to port it yet), batchrec does this. It still works with ALSA through the OSS emulation layer; adding native ALSA support is on my todo list for the next few months. You can grab it from http://www.physics.adelaide.edu.au/~jwoithe/batchrec-1.2.0.tgz It's pretty raw (no configure script yet) but shouldn't be too hard to compile on most systems. Batchrec can be requested to wait for signal above a certain amplitude before it records. It will also stop recording after the same threshold has been present for a user-specified time (if desired); at that point recording will stop, the file will be closed and the program will then wait for signal above the threshold again. I've used it extensively with analog inputs (hense the use of a threshold rather than exactly 0). The only fly in the ointment will be whether the SPDIF input on your soundcard can be mapped in the OSS emulation layer in such a way that OSS applications can use it. Regards jonathan