Stuck deflector in the discharge off the blower? I am not sure if the Vibe uses a cable driven or vacuum driven vent selector. If it is cable driven, may just be out of adjustment. On rare instances critters visiting your vehicle may have left a present keeping the deflector from moving all the way. Have you changed your cabin air filter recently? Replacement/access instructions should be listed in the owners manual, checking the filter may revel other surprises outside of cable adjustment. Was not able to find any pics of the deflector assembly for reference.
I haven't checked anything yet, I just got the car a month or so ago. I can figure out how to change the air filter but is checking the deflector hard to check?