maybe this is my problem, to test, where do I get a stiffer spring for my FV? Or is there a way to "shim it" to make it stiffer
its an action aluminum one with the stock spring, and retainer, in an AS nozzle (in case it matters)

The Nine Ball "Dyna" piston head sets come with a stiffer floating valve spring.

In my experience, those stiffer springs cause cycling problems in 90% of all scenarios. It's so stiff, that it doesn't allow the valve to close properly. This results in weak blowback and massive gas consumption.