I have the same problem on a system with RADEON HD 6450 graphics card; on my second computer with NVIDIA Geforce all is running flawless. Probably the issue is due to the RADEON module.
Regards Johannes-Heinrich Vogeler -- Dr. Johannes-Heinrich Vogeler Am Kiesgrund 16 b D-16548 Glienicke/Nordbahn e-mail: auc...@t-online.de