DE10-Nano HDMI_TX Demonstration Project -- audio not working. how do I fix / troubleshoot

Starting at 5.3 HDMI TX in the user manual

I ran the test.bat from the Demonstrations/FPGA/HDMI_TX project.

I can see the video pattern as depicted in the User Manual, but there's no audio, even after using the switch to enable/disable.

I then tried modifying the code so that the switch is always enabled and still no sound.

The pin assignments look correct in pin planner

HDMI_I2S -> PIN_T13

HDMI_LRCLK -> PIN_T11

HDMI_SCLK -> PIN_T12

I know that the device is capable of producing HDMI Audio, i have the mister retro project installed on an SD card and the hdmi audio/video work fine.