hello I am looking for a tutorial to change my cue button. I got an estimate from denon but they ask me 350 euros to change it.
bonjour je cherche un tutoriel pour chanegr mon bouton cue. j’i fais faire un devis chez denon mais ils medemandent 350 euros our le changer.
merci d’avance
Jérôme
No seriously… 350 euros 
to change a CUE button at this price I hope they take the opportunity to check them all and change them if necessary ??? 
Is go ahead with letting InMusic doing the repair. But as was said above, ask them to change all the buttons which you hit regularly
I think there is not really a tutorial out there. You could look at the prime 4 fix videos on Youtube to get a really brought understanding. I did some cue button and pitch fader fixing on a Pioneer DDJ SZ. I took apart the DDJ until i could free the Board where the button was located. I ordered the buttons online (not really expensive because they are used in almost every major product and are generic), tried to solder it by myself, made some mistakes eventually i just brought the the board and the button to some small electric repair shop and they soldered it. Put back together every thing and it worked fine.
My advice, if you have some skills you could
Overall costs should only be 20 bucks. However, if you did not do something before there is a high risk to destroy the machine and than it will be extra expensive. Since there is no tutorial you have to dig into the prime 2 to find out how to expose the cue button. Since you ask for a tutorial i have some thought you should leave it alone and bring it to a service shop.
If you have basic disassembly/soldering skills, you can change it yourself, or send it to any reputable eletronics shop. As far as I know it disassemble from the bottom. Take pics with your phone on every step and you should be fine.
Change all main switches and avoid disassembling again 