Hello & Welcome to Just Answer,
I'm Greg and will do my best to assist with this issue today.
Sorry I didn't see your question earlier and to hear of any issue you are having with your phones.
To help you with this issue, may I ask:
1) I noticed that you mentioned 3 cordless handsets but a -2 phone system model. So may I ask if this handset was an "add on" handset to the -2 system?
2) Does the noise CHANGE when the one handset is moved from one location to another?
3) Have the batteries in ANY of these handsets EVER been replaced - with NEW batteries?
Please REPLY using the box below and the SEND button.
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