I switched completely to Ubuntu 12.04 everything is fine instead when I play any track or video, the visual performance is good but the sounds flickers always and when I try to increase the volume it starts to flicker more. I installed Ubuntu restricted extras, checked my hardware, hardware drivers etc.
I had similar problems when using a USB DAC on an unpowered usb hub. Plugging the DAC straight into my laptop made it go away.
If you're not using an internal soundcard, consider whether your device is getting sufficient power, at least in my case, the DAC was just rebooting several times per second.