Burlington bathroom tap noise

[RoyWin]

I had new taps fitted within the last year on my bathroom sink. When turning on both the hot or cold tap, there is a vibration/squeaking noise, if the turn the tap fully on the noise stops. I have replaced the flexible hoses to both taps and fitted in-line isolation valves. The noise is now better but the isolation valves are barely open i.e the flow is slow. If I increase the flow the noise returns. Any advice would be appreciated. Thanks, Roy