Steve Walker wrote:

radio don't seem to bother matching the levels of guest and
presenter mics - no problem when sitting listening to the radio at home,
but with all the wind, engine and road noise in a car, the quiet guest
can't be heard

I listened to a political interview programme on R4 the other week

http://www.bbc.co.uk/programmes/b092fyw4

the format was quite annoying (for in-car listening at least) with the
interviewer's mic balance hard to the left, and interviewee's mic hard
to the right.