I have an IC-725 that seems nominal with light use.
However, if after a period of transmission, the overall temperature of the set increases,
a noise in the receiver starts and builds over a period of 30 seconds or so, blanking the
receiver and producing similar noise in the transmitted signal.

I suspect a synthesizer/PLL issue ?
Could this be related to the known PLL calibration issue ?

Regards,
Gary - G7TOK