My (Aug 2010) AVR600 has started to get extremely hot. Running for ca. 2 hrs at modest volumes, the top of the casework gets so hot (especially towards the rear), that I cannot touch it. It is in a cabinet with a lot of air around, and the lawn mower sound-alike fan starts up very frequently. Suddenly started to happen a week or so ago. Have informed dealer who is in touch with ARCAM. Any similar experiences?