Hey aucarre,
We want to confirm there’s only so much you can do before having to contact an authorized Roland dealer. What you can do on your own is documented in the SC-500 user manual, specifically starting in section “Cleaning the Printing Heads” (page 46). If you don’t have a copy of the manual, you can access it on the SC-500 support webpage here:
Roland Care Service & Support | Roland
If the issue continues after the cleanings, including maintenance cleanings, then the printer will require service. Call your dealer for repair.
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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