Hi
I have put together a video (45 minute long) about replacing the faulty encoders that are often a problem on the Origin desktop, I dont know about the keyboard version but the details would be similar apart from removing it from the keyboard but as i don't have one i cant show it.
The video is here on Youtube :
https://youtu.be/Gb4ko72mViMIn it I show the complete disassembley and putting back togther again.
I replaced all 33 encoders with the Bournes PE16 series encoders which are of a higher quality than to factory fitted Chinese ones but you might just want to replace a few.
I show which ones are needed, the tools to do it as well as some of the issues i faced doing the job.
Cost for the parts was approx $70 including shipping and tax to the UK from the USA.
The new encoders are made by Bournes and the part numbers are as follows.
3x PEC16-4220F-N0024
Dentent with No Switch
OSC waveform, Filter Type, LFO waveform
8x PEC16-4020F-S0024
No Detent with Switch
User white knobs around screen area
5x PEC16-4220F-S0024
Detent with Switch
Jog wheel, OSC select, Filter select, LFO select, ENV select
17x PEC16-4020F-N0024
No Detent with No Switch
Sequencer knobs and sequencer rate
I got them from
http://www.digikey.com/The datasheet on the Bournes encoders is here
https://www.bourns.com/pdfs/pec16.pdf