Graphical glitchs in Mario 64 (Parallel Core and Mupen64Plusnext)

I’m using the Parallel Core rather than the Mupen64Plus core as there’s weird black artifacting near the black borders at the top and bottom of the screen in that.

Parallel seems to be fine, except that when looking through a cannon, there’s a vertical line on the right side that shows you outside of the cannon, when it’s supposed to all be just the circular view in the middle. Does anyone know if this is fixable with some settings tweaks? I’m just using the defaults for the core.

If anyone knows about the Mupen64 problem too, here are examples of what’s happening with that core. (A small amount on the bottom of the first picture, and up where the castle is hitting the black bar in the second) This is present throughout the entire game while playing.