Weird city crash issue

[MightyPhred]

I have no idea whether the problem is with the game or my system, but I'm noticing that in every city siege my game crashes shortly after making first contact with the enemy in stage 1, I get about 10-15s of combat and then crash, after I relaunch the game it runs perfectly, no crashes, no lag, no graphics bugs (also worth noting that the game runs fine for me outside of cities, even at times of heavy actions like fort fights)

Several times I've now crashed the game deliberately while waiting for stage 1 to start and it seems to fix the issue, I'd guess I've done it about half a dozen times by now, I think there was one occasion when I subsequently crashed in stage 3, and on all other occasions the city siege has worked fine with no issues

also worth noting, I know that the contribution/loot system in cities is messed up but I always seem to be 24th place contribution whenever I crash in stage 1, no matter how much participation I put in after relaunching

any tech savvy person can explain/fix this? because it makes absolutely no sense to me