About 5 miles one way. That is pretty rough on your racing engine. It doesn't get hot enough to "burn" off the water caused by condensation, so you will need to change fluids every 3,000 miles and use light weight oil. The buzzing sounds like it is coming from a cold tranny, so check the fluid level and make sure it is pink.
You might want to consider down shifting to 3 or L, just to let the engine "breathe" some time during your commute and let the oil splash on to internal parts. Replace you air filter and cabin filter and with slow driving, you will need to clean the throttle body more often.

Klaus
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98 V70Rawd(101Kmi), 95 854T(85K mi), 75 164E(173K mi)