I noticed a distressing whineing noise from Kaito KA105, when the
whip antenna was retracted into the radio, and the radio set on
shortwave. This disappears as soon as the antenna is extended. On
opening the radio up, I noticed some sort of metal shielding in the
radio that would cover the antenna when the antenna is retracted into
the radio.
This would only happen on shortwave with the antenna retracted. I am
not sure if this is the same thing that is happening to you. Try
extending your whip and see if the sound disappears.
Hope that helps. - Cato