So, I seem to be a bit confused here. According to the documentation in audsrv.h, some functions will return an error code, some a status code, and some an error status code. There are only error codes listed in the header file. Should this be taken to be an oversight and they are all errors?
You should review the functionality of each function. Not all of them return the same thing. For example, audsrv_play_cd() will return a status code. It may be either a positive, non-error code (AUDSRV_ERR_NOERROR). Or an error code. Here, they don't have many cases where the function will return anything positive, other than AUDSRV_ERR_NOERROR.
My main concern is what is marked as error status code. I just need to know how to know if it should be " Now playing {track name}" or if it should self destruct lol. Also, as I side note, I'll correct any issues in the docstrings as I go through the header files. I've already noted a couple copypasta mistakes.
