Video won't play in preview window when audio output is DAC

Hi, new member here.

I had been having a LOT of trouble with FCPX - mostly since the last OS update. Videos would not play- they would TRY to play (the transport icon would change from ▶️ to ⏸) - but nothing would happen. It didn't matter if I was previewing the timeline, a clip, proxy or optimized. I fought this for a couple of days - reboots, PRAM resets, different drive, different users.

Then I switched from the DAC that I have been using (iFi Nano) back to the built-in optical on the iMac. Magically it just started working.

Does anyone else use an external DAC with their mac, and are you having the same issues? I really don't want to keep switching back and forth between outputs. Looking for any workarounds.

Thanks,

-jamie

I've always used Apogee products with no issues.

Interestingly - I saw that there was a firmware update on iFi's site ( ifi-audio.com/nano-idsd-ifi-xmos-firmware/ ) which I applied and it seems to be working again.

At least if it starts wiggin' out again I will (hopefully) remember what caused it the last time.