We have app_rpt : Issue #796 that reports a timestamp issue on reconnects. We recently submitted/merged a code change that should take care of this issue and it's possible it will also help out with what you are reporting. That change is included in the recent announced "beta" packages.
If you are comfortable trying out the early release, please have a look at the "beta" announcement.
But, if you are having issues with failed connections to any/every node then something else might be off. Have you checked to see that your node is successfully registering (e.g. sudo asterisk -x 'rpt show registrations')?