Sony Xperia z1 poor radio reception

I had my Xperia z1 for about 9 months now and a few days ago the radio signal just dropped out and now I can barely pick up radio stations without horrible static as if I was in an area with bad reception. I have looked around online and a few peoplehave had similar problems on Sony forums and they have no proper resolution or reason for it, just wondering if anyone on here has had a similar problem or could advise me what to do. I.have tried the usual fixes, different ear phones, off and on, clear data cache. I haven't bothered doing a factory restore to see if it changes anything yet though, I'm thinking it's a hardware problem at this stage but anyone have any more info?