I'd look higher up on the rafters and roof decking
from inside the attic for moisture and water stains.
water can enter high and exit low
the leak may be higher and running down to lower
roof where you see the leak.

best of luck

Thank you ... that is the first thing I did, went up to the attic with a flashlight and I didn't see any evidence of moisture at all ... I will check again tomorrow when there's a little more light.

Look at the connection points to the main house where the flashing is, that would be where I would start investigating.

I had the same problem in my prior house, and you could not see any obvious spot where water could get in. Unfortunately, the smallest crack (you can't see) will leak like crazy, especially under a steady rate of water. If you put a good tarp over it and it stops leaking, that obviously means it's the roof itself. I used rolled roofing and tar in my prior home to solve this. If the tarp does not solve the leak, I agree with millworkman and would add to check to see if there are any sections of siding that have cracks or gaps. and you see no evidence it
s running