PC3X

Hi, I just bought a used PC3X. It looks well looked after and sounds great and works reasonably well.
 I did notice that the screws to open it (two at each end on the rear have been used, possibly more than once judging by their wear) 
 I has the latest OS 2.21.  19920  
      
 I discovered several issues. 
 

 1. Editing Quick Access Banks causes the system to crash as soon as you save a patch in any of the 10 possible locations in any QA bank. The red light on the QA button stays lit. No others will work unless I restart.
 

 2. One of the headphone channels cuts out intermittently, often not for several hours, sometimes it comes and goes with crackles over several tens of seconds until staying dead. 
 

 The first time it cut out it worked again on restart.  Since then I discovered that when it cuts out a gentle upwards thump with my flat hand against the bottom panel just below the data dial will reconnect
 the cut out headphone channel.
 

 I was advised to do a factory reset to see if that cures the QA programming issue. 
 

 Which operating system will the keyboard have after that ? Will I have to re-install the latest O/S
 Which is the safest method to save the thousands of installed additional sounds which came with this unit when I bought it ?
 I was advised that using the self tests without training and data sheets is risky. True or false?
 

 

 Thanks in advance to anyone who can offer some reliable expertise to resolve the above issues.