Sony MU-R201 Reverb Repair

The Sony MU-R201 has always been one of my favorite "hidden gem" reverb units.  It has some small room and dual-reverb algorithms that sound extremely good.  I have some friends that also have this unit and they have had some problems.  Until recently, mine has operated flawlessly.  Mine developed an intermittent loss of audio with a low level digital noise and hum.  Lightly banging on the unit would bring it back to life for a few minutes.   I pulled the covers off (lots of screws) and did a visual inspection of that large circuit board.  You really have to look closely with a magnifier.  I found grounding solder joints that had given way either from vibration, heat or they were poorly soldered from the factory.  I sweat the joints pictured below.  They are part of a grounding rail system that is a strip on the top side of the board.  You can't miss them.  There are 3 of them.  That solved my problem and most of my friend's problems.  The unit is worth repairing. 
Good luck!