Troubleshooting NAD 356 BEE amplifier

I have a NAD C356BEE that turned itself off after 10 seconds and appears completely dead now - no standby light, nothing, it does however turn some parts of the PSU on and off as you can hear a faint click of a relay inside after pressing the rocker switch on the back of the unit.

The manual asks to check the +5V rails in case of no power and I've poked around with a DMM and the +5V rail appears spot on (no variation when pressing the power button)
But the "Standby" is at 2.6V. What would be the correct voltage at that point, also +5V.
 

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Please forgive me--- I may have steered you wrong. If you're seeing 2.675 on pin 3, it may asserted into the standby state by the processor. Given that observed voltage, do you find Q501 collector pulled to ground and relay RL51 turned off (i.e. correctly)?