Faulty Technics SX-PX663

[smith1990]

Dear all,

I've registered on here in the hop that someone may be able to assist me identifying the issue with my Technics SXPX663. I have no idea where to start when it comes to this, and unfortunately know very little about digital pianos in general.
Please check out the video I have taken of the issue in action!

http://tinypic.com/r/24pytlc/8

I have discovered, through trial and error, the piano functions perfectly on any voice setting excluding the Grand/Upright settings. The e-piano, harpsichord, strings, voice etc settings all work perfectly. As soon as I switch to Grand/Upright it crashes pretty much straight away! I have completed a factory reset by holding Mode Set + highest F# to no avail. I would assume this is a software issue as opposed to hardware, so I've no idea why the reset hasn't worked!

If anyone can offer any advice/guidance I would really appreciate it!