It ended up being the hub assembly. Supposedly it howled when part of the race came loose until the bearing chewed it all the way up, was my understanding. Either way, replacing the hub stopped the howl. Thanks for the replies!

My car runs and drives perfectly. A few weeks ago, it started howling (like a bearing howl) and it sounded like the driver front. We brought it in the shop to check and it just stopped howling. No change in driveability at all, no vibration, trans still shifts perfectly. After approximately 800 mile...