I had Sirius radio for a couple years, use Pandora now, and I had to do the same thing each year. Each year it was due, the subscription price would go way up from the "introductory price" I started with and I would just call and tell them I was dropping it if I didn't get it at the same price I had been paying. Every time they would reduce the price. Just make you go through the trouble of calling. I didn't use auto-pay and try to never do.
They aren't alone in the underhandedness. My Bassmaster membership automatically goes to auto-pay as soon as you pay even if it is manually. You have to call/email to tell them to take it off auto-pay, it is not on your online account. If my membership gets renewed automatically it is $30 if I do it manually it is $15 and you get some free chachke gifts supposedly worth $50. No gifts if it is auto.