Have recently been using the Teensy 3.5 (such a great little board) to control a fairly complex robotic vehicle. Some of the hardware in the vehicle includes 3x VESC's and motors, 2x Dynamixel servos, RC receiver, relays and other bits and bobs. Have been integrating the hardware bit by bit, ensuring that everything works correctly before adding the next piece of hardware. My last successful test included all of the hardware elements working together and everything appeared to be functioning fine.
So fast forward a couple of hours after doing some cable management, fastening down lids on the teensy's shielded enclosure and mounting electronics to vehicle chassis, and... the vehicle won't startup.
After hours of troubleshooting I have identified the following issues:
- Voltage regulator on teensy has failed. (Board won't turn on and regulator gets burning hot when teensy is plugged in. Also 3.3v pin appears to be shorted to GND)
- Voltage regulator on one of the VESC's has also failed. (Has the exact same symptoms as above.)

So the crux of my question is: Are there any common causes for the voltage regulators on multiple devices to fail at once?
Has anyone had something similar happen?

Heres some more info about my setup:
- Teensy and VESC's are all connected over UART
- Vehicle is powered by 12cell LiPo and has a dual output PSU (5v and 12v) to power teensy, servos and relays
- Everything was initially working prior to failure.
- The VESC which failed was connected to a long power cable (approx 600mm to battery)
- Nothing is visibly damaged (have looked closely at teensy and Vesc for burn marks etc)
- I accidentally connected 5v to the analog only pins on the teensy a few days before the failure occurred
- The grounds of the two power supply outputs are internally tied together. (After the failure I noticed that I had been channeling current from the 5v output of the PSU through the GND cable of the 12v output. Not sure if this may have caused the issue?)
- Happy to post pics of hardware/wiring if needed

I'm keen to hear any of your thoughts and thanks in advance!