VU5A not working on C0

[Ameridroid]

I've connected a VU5A to a C0 running Android 4.4.4. After booting, sometimes the touchscreen only works for a few seconds and then stops working. If I disconnect the USB cable from the VU5A and plug it back in, sometimes the touch starts working again. But eventually, the touch will stop working. I've tried 2 different C0 units and 2 different VU5A units and several different cables, plus 2 different power supplies.

Is this a known issue? Is there a solution?

[odroid]

Which power supply do you use with C0 and Vu5A?
Can you measure the voltage on the 5Volt rail of 40pin header?

[Ameridroid]

I am using the SmartPower (original model). 5.01VDC on the 40pin header. With the screen off, it is using about 3.3W of power with the battery fully charged. With the screen on, it is using 4.5W. At the USB input header on the VU5A, I read 4.8VDC.

[Ameridroid]

I've also added an additional 5VDC connection to the microUSB port labeled "DC" on the opposite end of the VU5A. No change. The touch works for a few seconds and then stops.

[Ameridroid]

I switched to a different C0 just now, and the touch works without problems. So the problem seems to be with that original C0.

[odroid]

Can you increase the SmartPower output voltage to 5.3Volt and test it again?

[rooted]

Can you increase the SmartPower output voltage to 5.3Volt and test it again?

It can only go to 5.25v without modification.

[odroid]

Yes, you are right.

[Ameridroid]

Those tests were done with the SmartPower at 5.25V.

[odroid]

Is the original C0 still having the touchscreen issue with 5.25V?

[Ameridroid]

It was. But when I carefully removed the heatsink from the original C0 to move it to the new C0, it pulled off one of the memory chips from the board. So I think that C0 is totally dead now.