I've noticed that the terminal audible bell sounds when the vim tagbar plugin first toggles on when I open a file. Subsequently toggling tagbar off and on again doesn't cause the audible bell. So, every time I open a source file, I get a bell sound; it's annoying.
I've turned off the audible bell for now in my terminal, so now I just get a visual bell instead (the terminal flashes momentarily every time I open a source file). This is livable, but I'd still like to get to the bottom of why a bell is being produced when the tagbar displays in vim.
I've turned on :TagbarDebug mode and pored through the tagbardebug.log. Nothing jumps out at me from that log file. I've also run vim with the -V option and pored through that debug output. The alarm bell sounds when the tagbar is toggled on, but there're no errors that stand out to me in vim's verbose output.
I'm using:
:: Update ::
I've learned that, when installed via Vundle, the problem with tagbar and the audible bell occurs. When I install tagbar manually into my .vim directory, the problem doesn't manifest.
Installing tagbar manually in the .vim directory or via another plugin manager — such as Pathogen — resolves the issue: no audible bell when when toggling on tagbar.
Apparently, there's a bad interaction between tagbar and Vundle. I opened up an issue in tagbar's issue tracker and the tagbar maintainer fixed the bug on October 28th, 2016.