My round sounds and other music wont work

Hey, I recently got a new computer and after downloading Gmod again, everytime I play TTT, start and end round sounds wont work. Please help. I got this error in console but I don’t know if it has anything to do with this

[lua][ERROR] lua/autorun/timeeffect.lua:17: attempt to call method ‘GetClass’ (a nil value)

  1. fn - lua/autorun/timeeffect.lua:17
  2. unknown - addons/ulib/lua/ulib/shared/hook.lua:183[/lua]

Post your code in [noparse][lua][/lua][/noparse] tags for us to tell you how to fix the error.

Done

Not the error, the actual script code.

No idea what a script code is ._.

The addon’s code. For example addons/end_round_music/lua/autorun/file.lua. Post the code to the round music addon.