When watching youtube, fast movement of mouse makes HDMI signal drop for a few seconds and then return? As long as the usb mouse is move really slow it will work fine, but very fast movement of usb mouse will cut out HDMI signal. I am using raspberry pi 400 image on a rasperry pi 4b. Any help would be much appreciated.
We have been struggling to decide how the mouse cursor was rendered in the Pi, with the current release, we are opting for the hardware-accelerated rendering of the mouse cursor, because if we don’t, the software-rendered mouse will experience significant lag when the system is under resources intensive tasks. We believe mouse cursor lag is an unacceptable deprive of user experience.
Hardware-accelerated rendered mouse-cursor requires GPU resources, especially if you make fast movement of the cursor, especially during YouTube video playback. Please remember it’s the Raspberry Pi, not a full-fledged computer, we only have so little resources to spare.
The ultimate solution is simple, don’t move your mouse when watching YouTube: Sit back, and relax 
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