Flatline problems

[Tracker]

i own a 68-4500 flatline, and the output is beyond inconsistant, it is set for like 800-900 (im not sure anymore) but the guage goes up over 1200, and then as i shoot it is bouncing from 600 to 800 psi, any suggesion on what the hell has gone so wrong? i have the newer style seat, have had the tank less than one year (brand new reg). cant think of anywhere better to post this than here. used to not be like this

Tracker

[Dayspring]

Replace the reg seat.

[Tracker]

grumble grumble that seems liek a pretty short life span on a reg seat

Tracker