I have the same problem, pixelation on itv 113. May be linked to the maintainance they carried out in our area yesterday which I was pre notified about by letter. Reset carried out and also tested V6 box using online test but still has a problem
Been happening here in BS34 (Bristol, North) all afternoon, on ITV HD chnl 113 and on Chnl 4HD 141.
Cant be bothered to phone 150 this eve as likely to eventually get through to call centre outside UK and they'll just go through a trained response. If still happening tom morn will call 150 and hope to reach UK.