Isspro EV boost gauge problems

[superduty4x4]

Hooked up my gauges about a week ago and the boost gauge wasn't working right. It will only read up to about 7 psi and starts making a buzzing sound around 5 psi. So tonight I decided to take it apart to troubleshoot things. All the fittings were tight (and Teflon taped), no kinks in the tubing. I took the gauge out of the pod and hooked it up to my air compressor set to 30 psi and was able to get 23 or so psi on the gauge, which seems fine considering I had a small leak in my jerry rigged setup. Any thoughts before I throw it back together to find out the gauge still isn't working right?

[superduty4x4]

Unplugged the MAP hose from the truck, plugged one end and put the Mityvac on the other end. PSI on the Mityvac gauge wasn't matching PSI on the boost gauge... it was reading about 1/2 of what the Mityvac showed. Looks like a bad gauge head I'd guess, gonna talk to Michael at Isspro to see if he has any suggestions.