Leeneia,

vaccuming an unplugged computer or other electronic device is unlikely to do any harm to it.

A MIDI controller sends MIDI data (not "music") to a MIDI interface. The latter can be realized by a "classical" MIDI plug or via USB. Either will work if the socket exists and is recognized by the OS (using specific "driver" software if needed). In case of USB ("U" for "Universal"), any version of Windows, Mac or Linux from this millennium does the job without problem, "plug-and-play". NWC may need a hint, typically something like a menu item "Options->MIDI Input->[x]USB".

Your controller seems to send unwanted MIDI note messages spontaneously, which result in "noise" from your computer loudspeakers because your OS is configured to turn any incoming MIDI data into reality (i.e. sound) immediately, besides sending it to MIDI software if "listening".