Head unit intermittently loses power when flashing headlights or using indicator

[Marbles]

Hey all - I'm experiencing a really weird (and frustrating!) intermittent issue and was wondering if anybody had heard of this before? Car is a 2020 Exige Sport 410 20th.

When driving and using the head unit, it will sometimes power off when I either flash the headlights to let someone out or use the indicators. When it happens, the head unit completely powers off (sound stops and all lights go out), then comes back on about 10 seconds later.

There doesn't seem to be any pattern to this - some journeys it will happen 4/5 times, others none. I've had it into Lotus Silverstone twice, but they have been unable to replicate the fault. They've done the basics - checking cables / reseating head unit / changing fuses etc. but with no success.

Any thoughts or experience?