Some ALSA apps stopped working

[Chris Lale <chrislale@untrammelled.co.uk>]

Some of my Etch sound apps have stopped working: Audacity, RealPlayer 10, XMMS.
Others continue to work OK: gxine, mplayer, VLC Media Player.

The error messages are:
	Audacity: There was an error initializing the audio i/o layer
	RealPlayer 10: Cannot open the audio device. Another application may be using it.
	XMMS: Couldn't open audio. Please check that: Your sound card is configured
properly. You have the correct output plugin selected. No other program is
blocking the soundcard.

I can fix XMMS by changing the output plugin from OSS to ALSA (right-click ->
Options -> Preferences -> Output Plugin. This should not be necessary - my Etch
laptop works perfectly through ALSA with the Output Plugin set to OSS.

I can fix RealPlayer and Audacity by installing alsa-oss and running them from a
terminal using "aoss realplay" and "aoss audacity". I am sure that this should
not be necessary either.

Can anyone please suggest where to look for the cause of the problem?

-- 
Chris.