PC. It's happen (for me) only in the "outer" circle of keeps (Rayles, Farragut, black boot etc) and only when the keep is under attack.
PC EU - PVP - CP 2300+Win 10 Home 64-bit - 32GB - SSD 1000GBIntel(R) Core(TM) i7-9700K CPU @ 3.60GHz (8 CPUs), ~3.6GHzNVIDIA GeForce RTX 2080 Ti