TAS2X63EVM: PPC3 Tuning Mode does not produce audio

Part Number: TAS2X63EVM
Other Parts Discussed in Thread: TAS2563

Tool/software:

I have the TAS2X63EVM board set up on my Windows machine (without the Learning Board), and it is capable of outputting audio over USB when PPC3 is put in "ROM mode". However in "Tuning Mode" no audio is being produced. Noticeably the PPC3 audio player seems to hang when in this mode -- it's stuck on 'playing' without the timeline actually progressing.

Have I misunderstood and perhaps require the Learning Board to use the tuning mode?

I have checked previous topics on this forum, and nothing stands out as exactly the same situation. I have verified that only the IRQ's live are 'PLL Lock' and 'Device Powerup'.

Thank you for your time.