I'm getting the same error that #4 is getting with a Samsung Galaxy S5 Mini on ubuntu 16.04. Like with OP, disabling USB debugging fixed the issue.
libmtp error: could not get object handles. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1232606 Title: Nautilus freezes accessing Android via MTP when USB debugging enabled To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/nautilus/+bug/1232606/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs