Since much of the noise on the radio comes from songs sung in Spanish, Catherine deduced that there could the true culprit MUST be Mexican. What does Catherine plan to do about this? She plans to "fire all the Mexicans and hire them back one by one until she finds out who is playing with the radio.
I've always known that I was dealing with stupid people but this is simply astounding.
Listen for yourself, the proofs in the pudding.