I finally got it working, but I wasted valuable time and money troubleshooting. I hope this helps someone else to avoid the same problem. After soldering the pins to the board and connecting, there was no way out. I checked with my microscope and the i2s data looked correct. It was only after purchasing a second board from another vendor (B07Q9K5MT8) that the problem (and solution) became apparent. In the photo, notice the 4 solder jumpers circled in red (and my embarrassing "baby-level" soldering ability)? They were not! I copied the jumper settings from the second board and everything worked. I'm an engineer but have very limited experience with EE so this problem and solution may be obvious to others. I don't mind if the board comes without a working configuration, but in that case we should at least have documentation about it. This would save a lot of time.
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