By disabling the touch screen controller, the USB transceiver errors disappear.
From our FAQ:
Device transceiver errors are triggered when the USB transceiver on the USB 2.0 loopback plug detects what it considers to be an error. These are events at a low level that may lead to the packet being retransmitted. They do not represent data errors at the application level. These errors are normally not visible to the user, but are displayed to help identify potential problems, for example, poor quality cables, cables that are too long, or system internals with insufficient electrical shielding with high electrical interference on the bus. Errors that may cause a device transceiver error are:
o Bad PID
o CRC error
o Bit stuff error
o Extra bits in a packet
o Full Speed EOP ending on K
o Loss of high-speed valid before EOP (truncated packet)
o Overflow (host clock running too fast or device clock running too slow)
o Token larger than 3 bytes (this may occur when using the USB 2.0 Loopback plug behind a hub, with Low/Full speed devices connected to the hub).
It should be noted that device transceiver errors are not an indication that the USB port does not comply with the USB Specification.
As it is a new design, I would investigate further with a USB protocol analyzer.
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