...it still seems to point to the tuner in the box being the issue, perhaps it's not as good as a tv tuner or maybe a little more sensitive to interference.
Indeed, when you have a (DVB-T/T2) tuner located within the same box as a WiFi receiver/sender the shielding has to be spot on.
Good cable management is also important. Indeed, a birds-nest of cables curled-up behind your A/V devices can all generate interference
I moved it to the conservatory which is fed from the same booster and quite a distance from the router, I re-tuned and now get 179 channels so yup something with the cable in the bedroom me thinks, could possibly be the mac and a small network swhich in the room next to it?
cheers everyone for taking the time to respond.... I'll try something different upstairs.