Every single program that Vorpx tries to hook in to crashes. VLC, MPC, xsplit (i know vorpx doesnt work with it, but vorpx still tries hooking in to it), and every directX game i own, both in and out of steam.
Tested with 0.6.0.0, 0.6.0.1, 0.7.0.0, and 0.8.0.0 runtimes. Tested with vorpx 0.9.1, not sure if this issue was there in 0.9, as the last one I used was 0.8.1. Did everything the Trouble Shooting Guide suggested said, as well as making sure i had all windows 7 (64 bit) updates as a certain forum post said. Using an Nvdia gtx 970 (have a 760 installed as well, but tested this with that card disabled).
Since vorpX apparently worked before and this happens to everything you try, it’s relatively safe to assume that some change to your PC caused this issue.
The No. 1 cause for such an issue are overzeleaus antivirus/security programs. So that’s something you should really triple check. Some av programs apparently don’t really disable themselves even when you tell them to do so. So uninstalling for testing purposes may be worth a try. BitDefender, Avast, Webroot are hot candidates for such odd behaviour, but there may be more.
If nothing helps, your best bet would be to go back to a Windows system restore point from before the issue started to occur and then go from there. With a bit of luck one is still present. Probably easier than trying to find the offending change to the system.