No need to apologize. Without your help I wouldn't have even had the courage to try the I2S pads at all, let alone knowing how to set up a voltage divider to make them work in the first place. This whole thing has been a great chance to learn new stuff that excites me. The stuff I've learned in this process, and your specific bits of advice along the way, is what made me cautious about the I2S lines at the end there, and to try different voltages for them to see if that would solve problems. That's why my last test with the lines connected straight was done with my hand on the power connector ready to yank it out at the first sign of trouble. That's what saved that most recent Betz board from being a third victim.

It's really good to know now, for sure, that it was the I2S voltage that fried the prior chips, and also that it was the source of some other problems I was having with the unit. With that all solved I've got much more confidence to move forward. And of course, it's going to help you quite a bit in your version of the project. Thanks for for putting it on the scope and getting a solid confirmation.




Alas, I cannot, because...



I need that USB port for debugging with the computer simultaneously while the unit is powered from its normal power source. A few different situations require this, not the least of which is having the empeg and the BlueGigaEmpeg both mounted in the trunk while I futz with debugging pairing/bootup/serial problems in the driver's seat. (I have a long USB cable run up from the trunk.)

However right now, with the 5v Pololu driving the Arduino VIN, everything is working fine, so I'm good with what I've got. It's awesome.