Unity, horizontal stripes under panel?

Question

linux

There is a Samsung R58 laptop with ATI X1250 video. The ubuntu 12.04 system (and on the previous ones, with the unit, as well). I observe stripes under the menu (the color changes on reboot), which, although they do not interfere with work, are very annoying ... Here is the screen .
Advise how to overcome.

Answer 1

I solved the problem a little radically by deleting /usr/share/unity/5/panel-shadow.png
Thanks, who, in a personal conversation, very clearly outlined the essence of the problem.

Answer 2

Which VM renders the desktop background? If nautilus, disable jpg rendering in compiz, if compiz, then leave it alone. Be sure to enable png rendering with compiz! Should help.

Answer 3

Judging by the fact that the color changes on reboot, it looks like garbage in the video buffer.
The Internet talks about different things, but the main point is that the free driver does not work correctly with 3D, at least with the part that Unity uses, and there is no proprietary driver.
By the way, some Internets say that you can get rid of the effect by disabling some of the parameters in xorg.conf, in particular, in some places they talk about disabling vsync .
Or you can try to switch to Unity2D