Why is rendered playback slower than my project? I have a project that's 1280X720 @25

I do have clips in the project that are various resolutions, but this hasnt seem to be a problem.

I render as the "Match the Project Settings" and everytime the video plays back much slower.

How to fix?!
Also sometimes my project becomes off time. But if I restart Vegas it fixes itself.
This was resolved due to incorrect audio sample rate with my DAW. In Vegas I was editing in 24 bit 48,000Hz. After render, my systems was attempting to playback the video file at 16bit 41,000Hz which will cause this effect.