Water supply question

I have a Delta single handle kitchen faucet (with a new repair kit installed). Here's what the problem is, the cold has great pressure, the hot starts out ok but tapers off, seems as if the water flow is restricted. As the hot side flows I can hear a slight single click when the water flow reduces. No kinks in the supply line, could the shut off valve in the supply line be bad? Thanks.

What brand of supply line are you using¿ Please don't say "flood stop."

The suppy lines are the flexible braided steel.

Not this one though, right:

No not that kind.