Scirocco Central

I've bought chinese Android head unit for VW. Overally very positively surprised, plug&play, fast as heck, CAN funcitonality (SW buttons, opening doors, reverse camera etc.) works, audio works, but there's a small problem with it.
When I'm turning ignition off, after a few seconds car is turning off Dynaudio AMP, therefore there's no sound from speakers while radio is still working and playing music. Turning ignition ON again sadly doesn't make AMP wake. I have to pull car key from the slot, put it back and then turn on ignition, that fixes it.
Sometimes you just go to shop with someone, turn ignition off and wait for them, listening to music. I can't do that and in addition if I forget about pulling key from slot first, and just drive away, I will not have sound until next key pull from slot.
I've already tried to solder AMP cable from radio to ACC (labeled "SAFE" on RCD510 cables sticker [and that's my current connection, no power drain so far) as well as simply to +12V from car. No difference.

I had RCD510 originally.
My CAN gateway is 1K0 907 530 Q.

Any ideas?

Anyone? Recently I've started my car and there was no sound. Had to turn it off, pull out the key and start again. So there is a pattern I've described above but there are also some quirks to that it seems...