I know that the poor radio quality is being worked on but it does seem to be very controller specific, some people are loud and clear and others are very hard to hear. I don't know if anyone else has noticed it but it seems to me that the controllers operating the more Northerly sectors seem clearer than than the Southerly ones. Perhaps some areas of the system are better than others.
The main problem on the flighdeck is the volume (gain I suppose really) of the transmissions. I find myself constantly adjusting the volume, other a/c come through very loud so you turn it down, then the controller speaks and you can't hear the message so you turn it back up, it gets very annoying after a while. Even with the volume up the a lot of the tranmissions sound "soft" and just don't seem to grab my attention anymore, I find myself missing calls because there is something else going on at the time.
I do hope it gets sorted soon, at the moment it is most unsatisfactory. London ATC have about the worst transmission quality of anybody I can think of in Europe at the moment.