Drakengard 3 sudden framrate drops and audio shutters

  RPCS3.log.gz (Size: 864.84 KB / Downloads: 0)
  RPCS3.log.gz (Size: 864.84 KB / Downloads: 0) I've been downloading a bunch of dlcs for drakengard 3, installing them without second thoughts. When I played the game though, framerates drop from 60fps to below 30 even 15fps when I tried to kill the minions along with the super annoying audio shutters. Before the crisis, the game worked perfectly fine without any issues at all.
So I desperately rollbacked my gameversion, reinstalled the game file, and even reinstalled the emulator but didnt work at all. The problem still persists after 2 hours of me struggling in vain.
besides, i've been getting a loads of red log lines like:
E sys_fs: 'sys_fs_stat' failed with 0x80010006 : CELL_ENOENT, “/dev_hdd0/game/BLUS31197DATA/USRDIR/FIOS-UNREALENGINE3/INSTALL/___LOCK” [1]
E sys_fs: 'sys_fs_stat' failed with 0x80010006 : CELL_ENOENT, “/dev_hdd0/game/BLUS31197/USRDIR/PATCH/INSTALL/___LOCK” [1]
and hundreds of these lines more...