Orange Pi Zero - dc-dc converter IC burned on PCB. Why and how to fix it?

besrunner

I attached non-powered USB hub to the unique and only USB port on Orange Pi Zero, and attached 2 webcams to the hub.
Everything worked find for hours and suddenly I noticed smoke came out of an IC on the Pi board, and jerked the OTG power plug off the Pi.
Hub stopped working. When I cracked it open HS8836 USB 2.0 controller IC had a small hump in the center and its facing inner wall of the housing melted a little bit. I could still power cellphone or something with the hub, but it doesn't provide webcam to be hubbed any more.
The smoking part on the Pi's board was 5 pin SOT IC and its arrangement with an inductance and capacitors and voltage dividing resistors told me that it's a kind of stepdown dc to dc voltage regulator.
Since then, I tried to connect the power source again, but as soon as the power goes on, parts around that regulator suddenly got very hot, so I unplugged the power again.
Plz tell me why this happens and why it burned the hub's IC as well.
And Is it OK for me to replace the regulator with other 1.5MHz dc-dc stepdown IC?
   

besrunner

I found out the part number and why this happens.

OTG power plug is somewhat defective that even with a slightest trembling causes the contact disconnected for a very short while. This causes the unstability of the voltage supplied to the regulator where it exploded with smoke. I tested with another Orange Pi Zero board, and found out OTG power plug of the new board is also very unstable. Only after connecting power to the 5V & GND pins, I could stop suffering from the unstable power disconnection.

If u consider to connect power to OTG plug, I'd like to advise u  not to do so.

Regarding the SOT regulator part, I found out this:

SY8008B SOT23-5 from <<User manual and Schematics.zip/User manual and Schematics/orange_pi-zero-v1_11.pdf>>