Expert: Cleggsan - 9/15/2008

Question
I have a SONY CMT-CP101 (micro hi-fi system) a few years old.  It has work faultlessly up till a few days ago.  When switching it on now I can only hear any sound when I put the volume control up to MAX, and then it is very faint but is coming through teh speakers.  I get no sound through headphones if I attach them.  After the system has been on for a while the suddenly kicks in and I can tune the volume up and down with the usual expected resonse and output.  If I switch off and then on again, of simply switch from CD to tuner, of even move to another CD track then the sound goes again only to return at an unspecified elapse of time.  When the sound has returned so long as I don't touch or change anything on the system it plays normally indefinately.
So the problem is intermittant and the symptoms leaves the system with only the faintest volume on MAXIMUM.  The speakers work fine on another system so they are not the problem.
Is there any chance I can do something to rectify this problem or is my much loved hi-fi likely to be like thid for evermore?

Answer
Thanks for your excellent description of the symptoms.  Based on what you described I am thinking it is an intermittent condition caused by a loose connection or cold solder joint inside the set.  Intermittent conditions can be sometimes easy to find and sometimes very difficult.

Here is what I suggest you try and then get back to me if it does not solve the matter:   Gently smack the set all around with your hand or fist.  Wiggle the wires and knobs and anything that is loose.  Pick the set up and move it around and then set it back down in its original position.  Doing this will often reactivate the bad connection.

If the characteristic of the symptoms change from the vibrations suggested above it is almost certain to be a bad internal connection and I hope you can get it working again without having to resort to a service expense.

Hope this helps.
C