I can hear a 'click' and the water runs slow. It is a high tap for the kitchen. No idea what brand but thinking Delta. The other water faucets in the house are fine. I cleaned the screens but think there must be some kind of mixing valve. I took the cartridges out and rinsed them. They appear to be in good shape but are 15 years old. I really can't buy new ones because of being unsure of the brand and water off sill sends some water through the stems into the sink.

So the question: Is there a mixing valve that moves and may be clogged?