Everything breaks after pausing and resuming syncing

[frankier]

I can't give the exact steps to reproduce, but this has happened more than once. Both times syncing begins correctly, then I pause it and resume it later (overnight). When I come back I see errors in the client about auth failing. When I visit the web interface in my browser I see a message:

Error: remote exception: expected result >= minBytes; Premature EOF
    at Error (native)
C++ location:(remote):??
type: failed

In the log file /opt/sandstorm/var/log/sandstorm.log - I see:

supervisor.keepAlive() failed. { [Error: remote exception: expected result >= minBytes; Premature EOF] cppFile: '(remote)', line: 0, kjType: 'failed' }
supervisor.keepAlive() failed. { [Error: remote exception: expected result >= minBytes; Premature EOF] cppFile: '(remote)', line: 0, kjType: 'failed' }
Exception while invoking method 'keepSessionAlive' Error: remote exception: expected result >= minBytes; Premature EOF
    at Object.Future.wait (/programs/server/node_modules/fibers/future.js:449:15)
    at waitPromise (imports/server/async-helpers.js:39:35)
    at [object Object].keepSessionAlive (server/proxy.js:474:9)
    at maybeAuditArgumentChecks (packages/ddp-server/livedata_server.js:1711:12)
    at packages/ddp-server/livedata_server.js:711:19
    at [object Object]._.extend.withValue (packages/meteor/dynamics_nodejs.js:56:1)
    at packages/ddp-server/livedata_server.js:709:40
    at [object Object]._.extend.withValue (packages/meteor/dynamics_nodejs.js:56:1)
    at packages/ddp-server/livedata_server.js:707:46
    at Session.method (packages/ddp-server/livedata_server.js:681:23)
    - - - - -
    at Error (native)

I realise this isn't yet a very good bug report, so please tell me if there are any additional logs or information I can give to help improve it.