@J7N Remember that I am a fan of dtsac3source and I recommend it when it's usefull.
The ideea was to play at the same time at least 2 different streams, AC3 or DTS. I also never experienced crashes, but to track down the problems, testing is a good way to go
As for Vista, at this moment, Vista XP64 SP1 it's the best OS in terms of stability, security and speed (if you can afford such hardware). I have some machines running it (but not with performance score under 5). The sole problem is that the file you downloaded it's for 32 bits and Vista didn't accepted. Let me find a 64 bit compilation and I will post it here. And..there is a new release of AC3Filter.