1.7.3 is out. This is again an experimental release, but it mostly contains bug fixes. It's been too long since the last release and some bug fixes that were too risky or extensive for 1.6.x had been piling up, so I decided to push it out. I've begun shunting new experimental features to a secondary branch and so the plan is to try to bake this code line until we can go stable again -- no new features. Please report any problems, and I'll do more experimental releases as necessary until the code line stabilizes.
The display code has been solidified a bit again and so a bunch of the refresh problems introduced from the multithreading experiments and the Vista DWM related tweaks should be gone. During the past couple months I'd been exercising the display code heavily in some other apps, which helped expose and wring out a number of bugs.
Notable new feature: I had gotten tired of constantly hacking my local build in order to play PS2 games on my laptop with low latency, so I implemented some DirectShow clocking options in the capture module. Disabling the clock is the one that helps turn your computer into an expensive television set, but there is now also an option to use audio timestamps. Previously VirtualDub always estimated audio timestamps from the CPU clock and the video clock, which was necessary under the VFW model; this was, however, not always very stable. The timestamps on the DirectShow audio samples can be considerably more accurate due to possibly being provided by the kernel driver. If you do video capture, go to Options > Timing and give it a whirl; it may make capturing more stable.