Air conditioner slight high pitch noise

[usernamex]

Hello,

I have a minor problem with two of my air conditioners. They are only 2.5 years old, Daikin model. They make a very sight high pitch noise (mostly seems to be the fan but even on the lowest fan level I can still detect it.) It would not bother most people and I've had the Daikin people in and they don't think it is a problem and the they say there is nothing they can do about it - typical response. However, the fact is that both units didn;t sound like this before and it annoys me. Anyone have an idea what it could be and/or how to fix it? Or do I just need to replace them?

Thanks in advance

[Pib]

If you are talking the inside unit it could be a dirty cage/roller fan. If talking the outside unit it could be the fan bearing.

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