Suddenly when I was playing music on my Nexus S it stopped playing all sounds through the handset speaker. It still works though if I use an external headset though.
I don't really have that much knowledge of the Android internal workings to see what the problem is, although I tried rebooting it.
I also can't really leave it for warranty repair because the boot-loader is unlocked (although I later reflashed back to the stock ROM).
fastboot oem lock
command.