Need help with RO solenoid shut-off

[TANGOMAN]

I'll try and answer the first question first... . The "fluttering sound" sounds like, well, fluttering. I dunno' ? Unfortunately I lack your ability to put sounds into a written form. If ya' put your tongue on the roof of your mouth and exhale allowing your tongue to flutter it makes a fluttering sound... How's that ? A Rattlesnake with a hair lip ?
You described the tubing I'm using though your color description is far superior to mine. It's the humidifier stuff. The valve controlling the inlet is a 1/4" ball valve, brass. Threaded, with adaptors, and soldered to a 1/2" house line. I got it from Hose Headquarters.
20g in a day ? Wholly crap !!! I'm evaping' a gallon a day...
I got a variety of the colored tubing with this RO unit. It looks impressive but probably serves the same purpose.
Us bald guys must refrain from banging our heads against brick walls as there is little protection up there and the scars just don't look cool on the skull...