Crashes and slow performance in menu's

played for 20h straight and only had 3 crashes. Today i have had 10 or more in the past 2 hours. running 32gb of ram, gtx 960 with a quad core intel i5 64bit system.

I am also getting horrible lag when opening my menu and trying to add or remove guns/mods. the actual game play is fine even with tons of mobs on screen.

and now it crashed but the game wont close

update: latest crash has now crashed my sound card and i cant get it back working.