New DDJ-FLX4 Sound Card Producing High Pitch Sound, No Audio

Does the FLX4 have a known issue with the sound card?

My equipment:

• Pioneer DDJ-FLX4
• Macbook Pro M1 16 inch / 16gb RAM
• Yamaha MG10XU with USB input

My DDJ-FLX4 is only a few months old, used 4 times total. When using the internal sound card with RCA outputs into Yamaha mixer, all I get is a high pitch, sort of squeal sound. Same sound is coming through the headphones i.e. cue channel.

If I reset Serato and use my Macbook Pro M1 USB-C output direct in to my Yamaha mixer, i.e. leveraging the Yamaha sound card, the controller portion of the FLX4 works fine. Just cannot use the internal sound card on the FLX4.

Never seen anything like this before so not familiar with this type of issue. Based on all of my trouble shooting, testing on multiple AC outlets in different locations, trying different computers, mixers, etc... the problem seems to be the FLX4 sound card.