It's about 15 years old now and running off an aerial in the loft. Quite often it seems unable to change to certain SD freeview stations. For example, one morning BBC1, 2 and ITV were fine but ch4, 5 and itv2 were blank. London live was fine, itv3 was blank and sky arts was fine. And so on. I ran the tuning set-up and all channels were fine. But next morning, the exact same problem returned; on retuning all was fine. Quite often i lose channels in the morning but then they appear again later on. It's very intermittent and unpredictable.
Can anyone tell me please if it's likely to be the set or the aerial an what steps i should take?