alsa stops suddenly.

[J B <bakshi12@gmail.com>]

Dear list,

My box is debian testing and I do upgrade S/w very frequently.
Since last few months I have not used any sound related operation,
but today I found that alsa is not working anymore.
I have checked with speaker-test and got the following

speaker-test 1.0.27.1

Playback device is default
Stream parameters are 48000Hz, S16_LE, 1 channels
Using 16 octaves of pink noise
ALSA lib pcm_dmix.c:1022:(snd_pcm_dmix_open) unable to open slave
Playback open error: -16,Device or resource busy

Could anyone please suggest a fix ?

Thanks