I tried QGC version “3.2.4 BlueRobotics Rev1” on three separate laptops- two running Windows 10 and one running Windows 7. The video “lag” looked like a variable speed output, where the video would fall behind by 2-4 seconds, then race to catch up to real-time, then fall behind again.
I just tried the version you linked above, “3.2.4 BlueRobotics Rev1 (Recording Disabled)”, and the video lag is different; it is a constant-speed display, but lagged by something like 0.75 - 1 second. By comparison, QGC v 126.96.36.199 gives us no visible lag or stutter, so that’s what we are currently using.
I also tried the tips from Bo (just on one Win10 laptop): there was no effect of battery power, no effect of changing font size, and the combinations of Nvidia settings I experimented with did not help. My settings did not exactly match Bo’s recommendations, in that there were program-specific options for designating the 3D processor, but not program-specific options for designating the PhysX processor… I’ll keep exploring that. But, the smooth and real-time performance we get from the old QGC makes me think it’s not just our hardware.