Can you determine where the issue lies more specifically?
If you connect it to the ethernet directly for instance can you play the videos?
Do you know if this this an Intel graphics chipset, NVIDIA, ATI, or something else? How old is the laptop?
Sounds like it might be the video chipset. You might be able to just disable that and use the CPU instead for video decoding if the system is fast enough. Or it could be that the system is using the CPU and it isn't sufficient for the decoding.
