Duplicate test results

Hi folks,

One of my test agents started reporting the test results twice, this is what it looks like in the logs:
[Step 1/1] MSTest
...
[Step 1/1] MSTest

The same project/configuration running on another agent doesn't exhibit this problem.
The build itself is a rake script, invoking MSTest via albacore. I have MSTest report watcher setup, removing it leaves me w/o test results in case of a failure.

Any suggestion?

Thanks,
ET.