Estimates are always loopy for the first couple frames with that client. I really should say "not available".
But could check the log file (IIRC fahlog.txt) to see if there are any error messages.
Also, if there were unexpected reboots (system crashes, power failures, etc.) the client could switch to a "safe" mode. That makes it significantly slower! (depends on the project but I've seen it taking twice as long in safe mode). To override safe mode, add -forceasm in the shortcut. Otherwise I'm not sure, but think that once a project is completely successfully it will return back to regular mode...?