experiencing some rather odd issues with Final Cut Pro, and a few mostly graphics-related annoyances

final cut pro:
after editing for a few hours straight, i must admit, the experience has been MILES better than my Early 2020 Intel MacBook Air (what originally started this whole macOS obsession), however i've also run into some issues. even though the experience would be fine for a while, it often stuttered and it has hung on me multiple times, at one point i even had to force quit it cause it wouldn't respond for 2 minuets straight. other than that, playback is fine and actually editing audio + not adding effects, but cutting videos has been great. however, when adding text, it keeps stuttering for 5 seconds and only then will it let me actually continue using the program. although, now that i'm writing this, it seems that in the middle of me typing it also seems to struggle to keep up, however this may be an issue with the fact that i'm using a SATA SSD (albeit a good one, a crucial mx500), as it was all i could get my hands on for now. i just want to be sure.

graphics issues:
it isn't really anything major, but every time it gets past the quarter of the loading bar, the whole screen turns back and i have to wait an extra 10-15 seconds for the login screen to appear. it sounds more like a first-world problem now that i'm here writing it out, but i want to fix that problem mostly for my peace of mind.
also, when i switch to another input on my monitor (using HDMI for macOS btw), the screen turns completely green and i can only get it to function once i unplug and plug my monitor back in. that's a weird issue that i've encountered multiple times now.

mild annoyance: iServices seem to work, apart from iMessage & Facetime. iCloud connected just fine, Notes sync fine, but iMessage refuses to send or receive messages. i've fixed my en0, set an actual ROM, checked my serial number everything seems to be great, and my apple account is NOT blocked. i don't know where to continue from here.

tl;dr: final cut pro stuttering & late boot black screen + green screen after changing inputs on monitor along with iMessage not receiving or sending messages concern user

apologies for the wall of text and for any mistakes in there, i wish you a good day.

specs:
CPU: Intel Core i5-12600K 10-Core (E-Cores are enabled)
GPU: Powercolor RX 6600 8GB
RAM: 16GB DDR4 3200MHz (XMP on)
Motherboard Model: ASRock H610M/HDV M.2
Storage: Crucial MX500 (500GB) (macOS) + Samsung 870 Evo 1TB (Windows)
Audio Codec: Realtek ALC897/887
Ethernet Card: Intel I297V
Wifi/BT Card: Intel AX200