Sounds like a classic case of friction and vibration. First, tighten every bolt and check the seals—any slack there turns into a hum. Make sure the hydraulic lines are properly clamped and that there are no kinks; a twisted line will buzz like a bad script. Lubricate the pump and cylinder with a high‑grade hydraulic oil, and keep the oil level exactly where the spec says it should be. Finally, isolate the base with vibration dampers so the noise doesn’t just amplify the whole unit. Keep everything tight, keep everything clean, and the lift will run smoother than a well‑optimized React component.

Sounds solid, just remember to let the oil warm up a bit before you start pulling torque – that can help the bearings settle and cut down the noise. Good luck!