So guys I've been dealing with this for HOURS! First post here after reading a lot and following all the steps. Finally bit the bullet and bought the
CableMatters 102101 so I could hook it up to my M2 Mac Mini. Flashed the firmware correctly on Windows (twice), double checked everything, hooked the M2 Mac mini up to my LG C1.
The chain goes: LG -> HDMI 2.1 -> CableMatters HMDI 2.1 to DP -> uGreen DP to USB-C (rated for 8K60/4K144) -> Mac Mini M2.
When hooking it up for the first time everything seems to work (4K60), I set the input to PC and switched the refresh rate to 120hz (which now became visible for the first time) only to get a black screen. It then does not revert and I have to use betterdisplay and the HDMI 2.0 port to get an image back by using betterdisplay's configuration protection.
Please help. I have the input set to PC, I have HDMI deep color enabled. All the HDMI 2.0 resolutions and refresh rates work (1080@120, 1440p@60, 4k@60) but as soon as I set it to 1440p@120 or 4k@120 I get a black screen.
Tried it with 3 different HDMI cables including the one I usually use with my PS5 (@4k120).
Also confirmed that my CableMatters adapter is indeed VMM7100 through the updater software.
Link to the uGreen:
https://www.amazon.nl/dp/B0C4DC6P4H?psc=1&ref=ppx_yo2ov_dt_b_product_details