Hi Rune,
We are facing the exactly same issue with the scheduler. This occurs randomly maybe with 10-20% of the scheduled runs. When the tasks are triggered by drag-and-dropping in Control Room, this never occurs. Also after the login agent, we can see that the resource is in ""Idle"" status and that the Resource PC is in mode ""Listener started."".
Which communication method you are using? We moved now from .Net Remoting to WFC. It seems to be more stable with WFC, but the change was just done, so it's too early to say yet.
Please, let me know, if you find any solution for the issue.