poor digital tv reception samsung error bit level but other tvs ok?

Hi - would really appreciate any assistance on this problem, been going round in circles trying to sort it.

My aerial (roof) is pointed to Wrekin transmitter (no engineering work going on)

We have a few tvs, different makes and models.

Aerial has splitter to these tv's. Having problems with poor freeview signal, keeps breaking up constantly on the Samsung tv's, but weirdly one of the Samsung tvs is fine. As is the Panasonic and another make.

So, unplugged the Samsung tv that is fine, brought it downstairs and plugged it into the aerial point where the other Samsung that is experiencing problems is. The tv I brought down is still fine.

So am now flummoxed - signal levels between 65-70, bit error levels between 3-10. Tried re-tuning, software upgrade etc. I would have assumed it was just the tv on its way out but 2 other Samsung tvs also playing up.

Help??? (please...) Thank you

Forgot to say - the reception on all tvs has been fine up until last few days, then Samsung tvs except one started to have digital freeview reception problems. Analogue and sky fine.