Sudden fps drop on specific boss , boss rush/chaos gate/secret map/ twisting chaos gate

do this problem get an attention ? its really annoying after valtan patch . the fps will drop down on specific boss like tarsila , tyr , even the pudge thing on last boss inside punika twisting chaos gate . i dont see any attention for post similar to this ? or fix ? its already like 3 maintance right ?
someone say try uninstall korean VO , already try it . but nothing change . before valtan patch i have no issue here. and this problem not everyone experiences it . :neutral_face: