Occasional enumeration fail -- where to look?

[bkaz4283]

Hello,

When I repeatedly unplug/plug in my USB device I find that it occasionally fails to enumerate. This device is running TinyUSB on a STM32H750VBT MCU. Here is the bus activity from USBlyzer when the device fails to enumerate:

And here is the beginning of the desired bus activity when the device enumerates properly:

Should I look somewhere in the software stack for the root cause of this issue? Or could it be a hardware issue?

Thanks,
-Brian