Kindle Paperwhite Ubuntu 14.04

Question

I recently bought a Kindle Paperwhite. On initial connection with my Ubuntu 14.04 laptop, I had no issues. The Kindle was mounted, and I put some ebooks on the device using Calibre. However, now I want to put some more books on there, but Ubuntu isn't picking up the device at all.

I have checked the USB ports and cable by booting into Windows, there the detection is immediate.

So something is wrong in my Ubuntu mount config (suddenly), but I have no idea what. (or why this happened at all).

EDIT dmesg output

[23446.135536] usb 3-1: new high-speed USB device number 57 using xhci_hcd
[23446.135565] usb 3-1: Device not responding to set address.
[23446.339387] usb 3-1: Device not responding to set address.
[23446.543246] usb 3-1: device not accepting address 57, error -71
[23446.839150] usb 3-1: new high-speed USB device number 59 using xhci_hcd
[23446.839221] usb 3-1: Device not responding to set address.
[23447.042998] usb 3-1: Device not responding to set address.
[23447.246854] usb 3-1: device not accepting address 59, error -71
[23447.542758] usb 3-1: new high-speed USB device number 61 using xhci_hcd
[23447.565721] usb 3-1: New USB device found, idVendor=1949, idProduct=0004
[23447.565725] usb 3-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[23447.565727] usb 3-1: Product: Amazon Kindle
[23447.565728] usb 3-1: Manufacturer: Amazon
[23447.565730] usb 3-1: SerialNumber: 90172202513702VR
[23447.568765] usb-storage 3-1:1.0: USB Mass Storage device detected
[23447.568969] scsi55 : usb-storage 3-1:1.0
[23447.643470] usb 3-1: USB disconnect, device number 61
[23447.914497] usb 3-1: new high-speed USB device number 62 using xhci_hcd
[23447.937547] usb 3-1: New USB device found, idVendor=1949, idProduct=0004
[23447.937556] usb 3-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[23447.937562] usb 3-1: Product: Amazon Kindle
[23447.937566] usb 3-1: Manufacturer: Amazon
[23447.937569] usb 3-1: SerialNumber: 90172202513702VR
[23447.944392] usb-storage 3-1:1.0: USB Mass Storage device detected
[23447.944628] scsi56 : usb-storage 3-1:1.0
[23448.016862] usb 3-1: USB disconnect, device number 62
[23448.286324] usb 3-1: new high-speed USB device number 63 using xhci_hcd
[23448.309293] usb 3-1: New USB device found, idVendor=1949, idProduct=0004
[23448.309302] usb 3-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[23448.309307] usb 3-1: Product: Amazon Kindle
[23448.309311] usb 3-1: Manufacturer: Amazon
[23448.309314] usb 3-1: SerialNumber: 90172202513702VR
[23448.312402] usb-storage 3-1:1.0: USB Mass Storage device detected
[23448.312724] scsi57 : usb-storage 3-1:1.0
[23448.342796] usb 3-1: USB disconnect, device number 63
[23448.614170] usb 3-1: new high-speed USB device number 64 using xhci_hcd
[23448.637279] usb 3-1: New USB device found, idVendor=1949, idProduct=0004
[23448.637289] usb 3-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[23448.637294] usb 3-1: Product: Amazon Kindle
[23448.637298] usb 3-1: Manufacturer: Amazon
[23448.637301] usb 3-1: SerialNumber: 90172202513702VR
[23448.640385] usb-storage 3-1:1.0: USB Mass Storage device detected
[23448.640692] scsi58 : usb-storage 3-1:1.0
[23449.271673] usb 3-1: USB disconnect, device number 64
[23449.541541] usb 3-1: new high-speed USB device number 65 using xhci_hcd
[23449.564621] usb 3-1: New USB device found, idVendor=1949, idProduct=0004
[23449.564626] usb 3-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[23449.564628] usb 3-1: Product: Amazon Kindle
[23449.564630] usb 3-1: Manufacturer: Amazon
[23449.564632] usb 3-1: SerialNumber: 90172202513702VR
[23449.567668] usb-storage 3-1:1.0: USB Mass Storage device detected
[23449.567921] scsi59 : usb-storage 3-1:1.0
[23449.867300] usb 3-1: USB disconnect, device number 65
[23450.137342] usb 3-1: new high-speed USB device number 66 using xhci_hcd

Based on this my guess would be that there is something wrong with the connection...