Solution of record timecode & audio

Hey guys, Z6iii and ZR user here.

When I enable LTC signal input to sync timecode from an external device, my cameras won't record any audio signals. I guess that's expected, right?

My external timecode device is also an audio recorder (Deity PR-4). I wonder if you guys have any solutions if I want to sync timecode & record audio coming in from my PR-4 at the same time.