Here is what I hope will be the final installment of my Battling iPhone's GSM Buzz series. It has become somewhat of an abiding obsession to outfit my G5 workstation with speakers that don't go rat-a-tat-tat every time my iPhone wants to talk to a cell tower. You readers have been very helpful with your suggestions, and I hope you've gotten some use out of my commentary (even if it's only Schadenfreude or commiseration).
Martin started me off on a new angle, and I commenced a search for a pair of computer speakers that could make use of my G5's optical audio out. I found them for a slight premium over my original budget of $100 in the Behringer MS40 Digital Monitor Speakers.