Can't hook specific functions

[eni9889]

Attempting to hook AudioServicesPlaySystemSound on iOS 9.3 and don't seem to be able to. Anyone else run into this issue?

[grp]

fishhook can only work for a subset of functions and function calls, since it depends on layers of indirection that aren't always applied. Without more details, it's hard to know if that's what's happening in your case, but here's a few places to start looking:

What code is calling that function that you're trying to hook? If it's system code, it might not go through the tables that fishhook patches, or even call the function directly.

Is fishhook able to find the function? Try putting some breakpoints or logging in the fishhook code and make sure it finds the function as expected.