Its a known bug and nobody really knows why. I asked Atle and he couldnt explain it himself...im searching for a fix since months now...i want to use the map for my server but not with that error =(

Oh man I forgot to close this one out, the issue was cleared after basically resetting my entire addon library, I've no clue what addon specifically caused it, as I wasn't interested in picking out 1-2 out of a series of over 500.

Really? And no idea which? i mean currently i dont have so many addons in gmod but still have it do you have a list of the mods you used? Maybe we can pinpoint it :D (going to make a list myself maybe you see something which you used too)

all my current addons https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=1745365858 (lot of maps which can be voided i guess just take a quick look maybe if you see something ^^ which you had but not anymore)

Just tested it yep its a addon....time to search (i thought i tested this before)

So i tested all have the same addons activated as before and ... it works now ... this is weird

Gotta love Heisenbugs, I don't really have the time to help search for this issue though, and my previous addon list is both not recorded anywhere, and too long to really pin anything down with.

Damned well so far it works for me :'D well maybe the only way to fix it is to just reinstall everything

For me it was wiremod messing up the camera.

i disabled it and it fixed it for me.

Ok I know this is old but the problem is clientside, not serverside
This means that it's an addon clientside that's causing the RT rendering error, maybe it's even the RT Camera addon

i'm experiencing this issue on my game, does anyone know how to fix it?