Note that second photo above: there is a clear plastic plate just sitting there, only gravity holding it in place. I think this is what may be wrong in your stalk: that plate may be in the wrong location or something.

The player does use all of the codes, but if you are happy without them, then just remap the working ones only:

[ir_translate]
KSOff=KOff
KSSource=KSource
KSAtt=KAtt
KSFront=KFront
KSNext=KNext
KSPrev=KPrev
KSVolUp=KVolUp
KSVolDown=KVolDown
KSRear=KRear
KSBottom=KBottom