Yup you have to enable audio out. However since my PC is also in my GroovyMame cabinet I just run audio out of my PC so I don’t need to deal with sending audio
On the note of lag. GroovyMame is laggier than GroovyMister in my setup which runs a 4th gen i5 … I can’t say with higher end PCs however, I haven’t tested. Calamity says you need a beefy PC to run GroovyMame with little lag.
Also consider the ease of setup when integrating CrtEmudriver compared to GroovyMister. I run both and enjoy both for their own reasons. GroovyMame benefits in my setup because it integrates with a front end and LEDBlinki which I’m now trying integrate into the GroovyMister setup. GroovyMister integrates the MISTers interface which is nice if you run games from the MiSTer
From my personal experience the lag coming from GroovyMister is noticeably less than my GroovyMame setup. To me less lag is more important than bells and whistles front ends and flashy buttons. So for now GroovyMister is my go to.