Hi, I too have the same problem. Can pass the re-newal test but not the initial. T'is a bumber indeed.
According to the CAA website, if you can pass the renwal test, they will 'discuss your options'. This means they are not automatically saying NO! Further research on the internet led me to believe that the CAA, in some cases, ask you to do a test similar to that of the FAA and stand, with your back facing the AME, to repeat numbers whispered by the medical examiner. If you can recal the numbers you are fine.
A friend of mine in the RAF (University Air Squadron) failed his hearing test and had to get checked out for neck and ears etc.. by a specialist and they passed him straight after his examination and now flys in the RAF.
I'm only 21 and want to become a commercal Pilot and my hearing is making me very nervous indeed. Until i had a hearing test i thought my hearing was spot on!
Anyway i hope this helps
Cpt Collins