Hi,
Is this happening on a new installation or Is it something that it was running fine earlier and started this lately ? Do you have enough RAM on the BI Server ..?
There may be many reasons why a service is not starting or having intermittent problems. One reason I would start looking at the allotted memory. BI Server is a resource hungry..., You must also tune services and allot enough memory to each so that it starts without issues.
Irfan