Start playing a movie. Pause it immediately.
Right click on the screen. Select DirectShow Filters>madVR. Click on the "user interface" item in the madVR settings, then press Ctrl-J.
Take a screen shot of the whole screen, showing the madVR statistics information. Post the image here, unless you can see an obvious problem.
Note, when I did the above for some movies using MC22.0.32, the video crashed when I pressed Ctrl-J. I was doing this one my MC Client, not the Server, in case that makes a difference. If that happens to you, you will have to hit Ctrl-J before the video playback crashes because of your problem, and then pause it afterward so that you can get the screen shot. If that proves difficult you can open the madVR settings page before starting the video by going to Options>Video>Open madVR settings. Leave the madVR settings page open, but close the MC Options dialogue window. The start your video playback, click on the "user interface" item in the madVR settings, press Ctrl-J, Pause (using the space bar is easiest and quickest), then take the screen shot.
See how you go with that.