Horrendous fps drop in Belkarth Outlaws Refuge on PC/EU

BreacaT

Recently I've started using the outlaws refuge in Belkarth, but for some reason I get horrendous fps drop inside of it, like from 60+fps to somewhere between 10 and less than 1. The moment I exit then the fps picks back up again. I don't notice this anywhere else (Cyrodil aside) and it doesn't happen when I play on the Mac, which obviously has completely different hardware but does have the same add-ons. Of course, the easy option is not to visit this particular refuge as it's the only one that causes a problem for me.