Squeaky sound...flatline tank?

[X-Plosive]

I am trying to determine whether the squeaky sound is comig from the gun or the tank but I am pretty sure it is the flatline. After every shot I hear a small squeaky sound for about a second and thta it goes away until the next shot. It also makes this sound when the gun is being gassed up. Any help? Maybe I'll try that flatline reg maintenance.

[BlackVCG]

That's normal. I believe it's the sound of the piston moving back and forth. Put some light grease like Dow33 on it and that should help. KC N2 oil is very slick and should do the trick too.

[X-Plosive]

I already put DOW 33 on it, that stopped it. It's the most annoying sound on earth, like a cat moaning.