I had similar issues with my Xedos when it was 13/14 years old - I disconnected the aerial connection from the back of the radio - gave it a rub with emery paper - solved the issue.

The aerial was an electric on the rear wing and access to that would have been troublesome so grateful it was easily fixed.

Tried a new aerial from Amazon at £5.99 and it fixed the problem.
The car is 17years old but I’m still planning a warranty claim on Toyota !!

Things aren’t suppose to break on a Toyota !