Have the Cranfield frequency (along with all others) checked in the set. Depending on what type of radio you have fitted as some are worse than others,you will probably find the frequencies have wandered off a bit and the set needs re tuning. Usually more noticable on any frequency where the signal strength is lower such as distance from transmitter, terrain, etc.Another cause could be it is down on power. Often sets have dual power supplies ie 12volt+ and 12volt- powering them and one leg could be down often caused by capacitors in the set drying out. These will need replacing if the case.
The antenna can also be the culprit so have a SWER test done on that too.
Either way you need take your aircraft to a radio shop and have it checked out.
Last edited by mostlytossas; 30th Sep 2013 at 09:54.