Sony CMT-CP11 Hi Fi


This little set was installed in our kitchen.  The speakers were installed above the kitchen cabinets,  covered in cling-film to protect them from the grease and dust which collects up there - this did not seem to affect their performance.  We bought a Sony as a previous Hi Fi is still running fine after more than 20 years.

Plus side:  the audio quality is excellent;  the FM tuner is excellent (isn't ANALOGUE wonderful!).

Minus side:  it does not switch on immediately,  preferring to display an irritating welcome message first (Share & Enjoy!).  It loses all its channel settings after a few days disconnected from the mains.  The remote is a typical tecchy,  unfriendly digital interface.


After a few months fault-free performance,  it went dead,  with no evidence of power to the device.  Coincidentally,  the mains circuit-breaker tripped out,  isolating the kitchen (including the fridge-freezer!).  The fuse in the mains lead  to the CMT-CP11 was intact.

On returning the unit to the dealer,  they replaced an internal fuse at no charge.

About 6 months later the same happened.  This time the dealer replaced the unit.

Some months later the same thing happened.  Again,  the internal fuse was replaced.


I would guess this unit has a switch-mode power supply.  Perhaps occasionally a mains spike causes a temporary overload and blows the fuse.  The CMT-CP11 requires to be connected to the mains all the time - if it is disconnected,  it looses all its channel settings after a few days (we have never bothered setting the clock!).

No other equipment in the house exhibits this sort of problem.

Perhaps the mains filtering/voltage limiting is rather poor in this design?  Perhaps the power supply is rather close-tolerance?

A unit which requires to be connected to the mains all the time aught to be particularly tolerant of dirty mains.


There is a tendency for new devices not to allow the user to disconnect them from the mains supply without inconvenience.  (However our old Grundig VCR had battery backup for its memory - so why cannot other manufacturers do this).  There is a good safety case for disconnecting devices from the mains when not in use.  There must be a few power stations kept busy powering domestic devices which are in effect switched off!