Comment 3 for bug 81843

>I suspect this is an OpenAL-related issue. Did you already try changing
>the output driver of the OpenAL HAL according to
><http://supertux.lethargik.org/wiki/Tips_and_Tricks> or
><http://supertux.lethargik.org/wiki/OpenAL_Configuration#Examples>?

Thank you for the reference. I looked there and, after some
experiments, I found that this configuration works for me:

================ /etc/openalrc ================
(define devices '(esd alsa native null))
(define alsa-out-device "default")
#(define alsa-out-device "output")
(define samplig-rate 44100)
(define speaker-num 2)
===============================================

Now the bug as described has gone.