Has anyone had any problems with the windows stunnel service not starting automatically?

We install stunnel as a service (stunnel.exe -install) We've had it previously installed on 600+ machines with no problems, but recently (noticed on slower machines running XP) the stunnel service does not start...but it happens randomly only on slower machines. The following errors are in the event log...

Timeout (30000 milliseconds) waiting for the stunnel service to connect. (Event ID ID 7009) AND The stunnel service failed to start due to the following error: The service did not respond to the start or control request in a timely fashion. (Event ID 7000)

I've tried setting the service to restart if failed, and to delay 2 minutes before restart, etc with no luck. If you start the stunnel manually all is well, it just doesn't start on bootup.

Any suggestions?

Thanks

JP