Hey enzo972,
We don't have a documented procedure for this repair/replacement. Dealers are training on how to repair/replace parts, so it's recommended that you consult with the dealer that sold you the part. They should be able to help you.
If you have additional questions or need extra support directly from Roland corporate support, please submit an "official" support request form online here:
Product Support Form | Roland
If you do write us, we look forward to helping you and take care,
Roland Technical Support
Roland DGA Corp.
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