If there are suggestions regarding driver or settings, I can try them today in the evening. But in general CUDA is working, seems for me to be cause by a difference between how Haali and TsReader handle the TS.
Probably MP's rendering is more GPU intensive than just plain video renderer used when you play inside graphedit. Rename the .ts to .mkv and play inside my movies plugin. It will cause haali (or any other source filter that your system has installed to be used instead of TsReader).