android phone mtp automatically unmounts on connecting

[sn0m]

Hi
I have an HTC1 M8 that up to know I have been able to connect it to my Lubuntu and transfer music and so on.
Today I don't seem to be able to.
Whenever I connect, I get the message that it has been unmounted successfully. If I try to mount it manually, I get the message:
" Error initialising camera: -53: Could not claim the USB device" and it would not mount.
I'd appreciate it if this could be sorted out.
Many thanks
Sokol

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: android (not installed)
ProcVersionSignature: Ubuntu 3.13.0-52.86-generic 3.13.11-ckt18
Uname: Linux 3.13.0-52-generic i686
NonfreeKernelModules: wl
ApportVersion: 2.14.1-0ubuntu3.10
Architecture: i386
CurrentDesktop: LXDE
Date: Sat May 9 07:09:47 2015
InstallationDate: Installed on 2014-10-31 (189 days ago)
InstallationMedia: Lubuntu 14.04.1 LTS "Trusty Tahr" - Release i386 (20140722.2)
SourcePackage: android
UpgradeStatus: No upgrade log present (probably fresh install)