Not even FPS changes can produce Variable Frame Rate — this bug has existed since the implementation of MPlayer. TVAI 5.3.6 was the last version without VFR issues.
So, if you convert, for example, 25 to 50 FPS or 30 to 60 FPS without activating “Replace Frame” in the new Topaz Video AI, you will get ok CFR, but for all other, non-even FPS conversions, you should use version 5.3.6 or below. It’s a real shame that Topaz has never been able to fully fix the VFR problem. Luckily, you can install TVAI 5.3.6 alongside Topaz Video, and then simply use whichever version fits the situation.
