My wife's 2000 LX has about 22,000 miles. On our recent short road trip, I noticed that the OEM Firestone Affinity tires have become very noisy -- you know, the rumbling sound. I have rotated these tires according to the maintenance schedule and both fronts and rears have worn evenly. Have others noticed this? If the noise continues to degrade, I'm going to have to get new tires earlier than my usual 40-50K life. Are there alternatives other than the Firestones (never again) or the Michelin Symmetrys?