Help with weird noise in SPA 303 - 7.5.5

[Diego Betancor]

Hi,

a customer has 4 SPA 303 - 7.5.5 all the same. In one there is this little noise/pitch like an interference, only in one of the four, the other three are4 OK. I included a mp3 file (in spanish) to hear the sound.

Any idea, I would really appreciate. Thank you, Diego

[Dan Lukes]

It sounds familiar to me. It's GSM phone interference - listen and compare here. It's caused by mobile phone placed near other wires.

[Diego Betancor]

Thank you so much. I think you are right, I remember now that sound. I will contact the customer to look for the GSM. Thank you again, Diego