Joe, thank you for that, I did suspect they were voltage regulators of some kind as the tracks around the IC were quite thick, suggesting a reasonable current carrying capacity.
I found a photo on the fccid.io page showing the internal pcb's, it looks like a pre-production model but the interesting bit is this
Which shows two regulator sub pcb's one is 8v and the other, which is the one that gets hot in my radio is 3v3.
Just need to find out what the device is now, which is proving to be quite a challange.
Tony G1HMO
