Could you please attach CC (CC1/CC2) scope waveform also? You can remove USB_VBUS (magenta) or VSYS if you only 4 channel.
Could you please share CC log of this case?
Could you please use UART to transmit the hard-reset reason with firmware debug?
I think my chip may have been damaged by over-temperature. I'm currently using CYPD3120-40LQXI. I see in the datasheet there is an extended industrial range for the CYPD3135-40LQXQ. Can I use this as a replacement for my upstream facing USB 3.1 Gen 1 device?
My CC analyzer is broke. I should have a new one in a couple days to get CC log.
We discovered that the wrong capacitor had been used for the VCCD pin. It was too small a value and had too much variance with temperature. After replacing the capacitor the problem is no longer reproducible.