1 Printer of 7 will not communicate

3dForge

I've set up my 8 printers on 2 pi severs over the last few days. I'm very happy with the server software, but I cannot get one of my PRUSA MK3s working. 

I see the port on the pi, I've tried multiple USB cables, USB ports, and hubs. All of which work on other printers. I can plug this MK3 in to my PC and connect to it through SLIC3R, I updated the firmware, just in case. I have 3 other MK3s working fine. If I unplug this printer and move the cable to another printer it works. This makes it seem like an issue with the printer itself, just want to confirm before I complain to PRUSA.

This is a copy of the console readout that seems to apply to the issue.

3:15:48.098: N1 M110
3:15:48.098: N3 M115
3:15:48.098: N4 M220 S100
3:15:48.098: N5 M221 S100
3:15:48.099: N6 G92 E0
3:15:48.099: N7 G90
3:15:48.099: N8 M82
3:15:48.099: N9 G21
3:16:19.108: Warning: Communication timeout - resetting communication buffer.
3:16:19.108: Connection status: Buffered:110, Manual Commands: 3, Job Commands: 0
3:16:19.109: Buffer used:110 Enforced free byte:22 lines stored:9
3:16:19.112: M117 IP:192.168.1.232 (2)

Repetier

I also have a MK3 with einsy board. It has the bad habbit to show the usb port even if the printer/firmware is not running, so server will try to connect and fail with timeout. Check in printer settings "Printer is visible even if firmware is not running". That will suppress connection try messages until it really succeeds. To make it work you need to enable main power, then connection should work.
When you can upload firmware and display works there is no hardware problem I think. Have you selected Marlin as firmware? With repetier-firmware selected you also get no communication. And baud rate should be 115200. These are the 2 main things in server that could prevent success on connection apart from using wrong usb port. Especially if you have 2 identical printers they might have same id so you should connect port by path so usb port connected matters.