The loud noise & vibrating could be due to the "harmonic resonance" between the RO system & your house. This happens sometimes when the system's frequency resonates with your house's natural frequency. Please try the following and see if the noise & vibration will go away:
- Put some kind of padded cushion (foam pad is OK) under the RO system & against the cabinet wall so that the system is padded, this should break up the resonance and help reduce the vibrating.
- Do not mount the RO on anything, let it stand free will help too.
Please try that and see if it fixes the problem.
