There is a well known bug with OpenAL causing multiple sound drivers to fight with each other when playing sound in Linux.
For details see:http://sourceforge.net/tracker/?func=detail&aid=2792509&group_id=127297&atid=709610https://bugs.launchpad.net/ubuntu/+source/openal-soft/+bug/503780
While there are newer versions of OpenaL that "claim" to fix this, I have fixed glest and all of my other sound problems in Ubutnu by doing this:
#1 Edit the Open AL config:
sudo gedit /etc/openal/alsoft.conf
#2: Ensure you have a line with (at least) the following:
drivers = pulse,alsa,oss
(make sure the first character is NOT # or it means its commented out)
Save the file.
#3: kill pulse audio by running:
#4: restart pulse audio via:
Edit: Here is a bash script to automate it:
# now deal with the openal library [libopenal.so.0]
hasdrivers=`grep "^[d]rivers" /etc/openal/alsoft.conf`
echo "openal drivers = [$hasdrivers]"
if [ -n "$hasdrivers" ]; then
echo "openal drivers was found = [$hasdrivers]"
echo "openal drivers is missing, attempting to setup a working configuration"
sudo cp /etc/openal/alsoft.conf /etc/openal/alsoft.conf.bkp
sudo sh -c 'echo "drivers = pulse,alsa,oss" >> /etc/openal/alsoft.conf'
echo "openal re-configured, try out your sound now!"