Conga and bongo parts on a single staff?

I'd like to write a conga/bongo part on a single staff, since they'll be played by the same person, at the same time. Is there a simple way to do this? I don't mind just writing both parts on a four line conga staff, but then, I'm having issues with playback.

So, either a way to combine 2 staves, or a way I can manually change the playback sounds