problem with CO2 Regulator

[Canadian Man]

I have a SWC regulator with the built in bubblecounte. I just got my 20lb bottle refilled and they had to change the valve as they said it was bent. $114 later I hooked it all back up and everything seemed to be working fine.

The problem I am having is that after about 8 hours the bubble rate has dropped considerably. I usually run about 200bpm and it slows down to about 60bpm.

The cylinder pressure is constant 800ish psi and my working pressure is constant.. I usually run it at 10 to 20 psi.
So every day I have to fiddle with my bubble counter to increase the bubble rate. Any ideas?

Thanks