Try opening the sunroof completely...and checking all the way arond the inside where it mounts into the roof......seals shrink over time around the glass as well....between hot ,cold, sunlight, shade, weather.....etc.,,

Automatic Cawashes use pretty harsh detergents and degreasers to get ur car clean as well...(If you have gone that route)
you really have to look into harshly(disassembly) to discover what or where its comeing from....the glass where it mounts into the frame could also be the culprit.....look for any signs of rust or corrotion there too..
there isnt always a "quick" fix.....is it power? , manual?, factory, or aftermarket?

Mine has the power "Moon" roof...from the factory

 

Yah i got the same problem in my 03 ss i suspected it was the sunroof right away. the weatherstripping seems solid and even when i slide the roof back theres no trace of water. but i still seem to leak water out of my compass /temperature winshield console . so thats what im suspecting even though its stock i think thats where its coming from . i do have a system and i do notice the bass traveling towards my upper winshield maybe th
ats what couldve caused my winshield leak. i havent fixed it yet so if someone does let me know.