Other than unckecking the "Start Dbpoweramp when windows starts" check box in the Dbpoweramp configuration, I don't think you can shut off just the MMC window.
I wasn't sure if Alteclansing was having problems with MMC starting up at the same time as dAP or not. If MMC was open when you shut down dAP does it start automatically the next time dAP is started?
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