Venue 11 Pro travel keyboard - touchpad initialization issue

Hi,

I recently bought an Venue 11 Pro 7140 and am having some intermittent issues with the touchpad, similar to issues reported by some others here. Basically:

* If the battery inside the travel keyboard is flat or disconnected, the touchpad works reliably.
* If I keep charge in the keyboard battery, I have intermittent problems with the touchpad not sending any touch events (even though the USB HID part works fine and I can even run the MSP430 firmware update utility).

I probed the 6-pin connector that presumably goes to the touchpad and found the following:

* With the tablet disconnected, the 3.3V rail seems to be floating at around 2.0V.
* After connecting the tablet, it comes up to 3.3V.
* However, pin 3 of that connector is now low whereas it's normally high when the touchpad is working normally.

My battery voltage is about 7.8V so seems to be fine.

I assume that, with the tablet disconnected, either (a) the touchpad is meant to be off and it's being back-powered with 2V through some path, which might be putting it into a bad state, or (b) it's meant to be on and I have a power supply issue.

Before I dig further, does anyone have any more insight based on this data, either via inside information or probing their own unit?

Matt