That sounds like a printer. Specifically, linefeed sounds like a good old 66 lines per page line printer (printing on continous forms), as we used 20 years ago. But I didn't know those had a control panel.
Can you tell more, including the solutions you tried but didn't work?
I am constantly plagued with linefeed and page feed not working. I've looked through the control panel for a solution but those I've tried didn't work.