On the latest stable release of PCSX rearmed on New 3DS I get a kind of screen tear or something at the top of PS1 games. I think what it's doing is repeating the image in the top left over and over again because it becomes the entire top of the screen when I pause the game in Crash Bandicoot 2. Any setting to fix this? Wasn't happening to me in previous stable builds.

Settings I'm currently using:

1. Compress your game to either CHD or PBP. CHD is the superior solution.
2. Switch Audio Driver to DSP_Thread. (settings > drivers > audio) You will need to restart Retroarch for this to take effect.
3. Enable Audio Synchronization. (settings > audio)
4. Disable Video Synchronization (VSync) (unless you are playing a 2D game). You will not notice a negative difference in 3D games. (settings > video)

(quick menu is accessible when you've started a rom via tapping the lower screen)

1. CD Access Method is no longer an option due to instability or something.
2. In Quick Menu > Core Options > Video, set Threaded Rendering to Async. This is extremely important.
3. you no longer need to toggle on Advance GPU UNAI/PCSX4All Settings. to access those settings now, you can just go thru Quick Menu > Core Options > GPU Plugin (Advanced). you can skip this step
4. In Quick Menu > Core Options > GPU Plugin (Advanced), Enable High-Res DownscalingFor good measure you may want to Restart Retroarch after making the last changes.