Comment 9 for bug 1309488

Hey Frank, did your problem start after the upgrade to 14.04?
If so we might have a similar, if not the same problem:
https://bugs.launchpad.net/ubuntu/+source/pulseaudio/+bug/1310260

Could you post the output of:
sudo cat /sys/kernel/debug/vgaswitcheroo/switch

to see if your AMD GPU get's switched off as well?

Thanks