As an update on the subject - it seems that the latest Catalyst drivers (10.3) fixed it. To validate this, I re-installed 10.2 and tried again and indeed there is something (which isn't directly mentioned in the release notes of the 10.3 fixes) that causes the same problem to occur, so 10.3 it is.

Thanks again for your time!

Hi xaotik, that's great news that the updated driver has fixed the problem!

Video cards these days tend to be the most complex thing in your machine, and the video drivers are a set of complex software as well. Complexity tends to breed bugs so that's why it's not too unusual to run into bugs in video drivers more often than in other kinds of drivers.

- Michael