Hi Fi repairs

I am an elderly and totally non technical individual, and recently, but
quite characteristically managed to muck up the settings for the
dvd/amplifier connection in my system. Thos was set up for me by a friend
who is now overseas. I rang a local (Camden Town) Hi Fi shop and asked
their rates. Minimum call out $47.50 plus VAT, and £1 per minute after 20
minutes! Quite apart from the cost being prohibitive, if the man comes out
and is incompetent, he can charge for his own lack of skill!
Does anyone know of someone who would be reasonable in their charges? I
stress that almost certainly this is a 5 minute job, occasioned by my
abysmal ignorance. Even if it cost £30 or £40 I wouldn't mind, but an open
chequw is out of the qiestion for an OAP.

Thanks

Peter Cartwright 0207 2094162