Oh, one other thing which could potentially be causing you problems.
When you're using anything other than HDMI, your video and audio will be out of sync. (HDMI should be able to keep things in sync with recent hardware)
The display will have some amount of latency, and this may vary depending on the refresh rate being displayed, and the options you have enabled. (e.g. motion interpolation often adds 100ms+ when enabled)
You audio hardware will also be adding some amount of latency, and this likely varies depending on the sample rate being played. With an ASIO buffer size of 8192 samples, 44.1kHz audio will have a latency of 186ms, and 192kHz audio will have a latency of 43ms. I upsample everything to 192kHz to prevent this from changing.
And Media Center/the PC itself will have some amount of latency being added as well.
This could easily add up to over 200ms. In my case, it all adds up to 136ms for video playback. (when my TV is in "Film mode" rather than "PC/Game" mode where it's <30ms)