My 552 has been reinstalled this morning after dropping the left channel and is warming up nicely.
Naim have done a cracking job including replacing the the Volume and Balance Knobs as they said they were slightly discoloured ?? they also realigned the balance control. The channel problem was a relay.
When the 552 packed up the dealer installed a 282 the following day for me to use whilst the 552 was away.
A big thank you to Audience Bath and Naim Audio for this excellent service anyway back to the music.