ronsonrough031011_01_X17230WM.jpgAfter her early morning arrest for DUI In Baker, California, Samantha Ronson called in sick to her scheduled DJ gig last night at The Brig in Venice.

Our source tells us she told club bosses she "had a rough day and won't be able to make it." Three hours behind bars sounds pretty rough to us, too!

We're also told the fill-in DJ made the announcement over the mic that Sam wasn't going to be spinning for them, and unfortunately the crowd had no reaction. Ouch!

The 33-year-old DJ was pulled over by the California Highway Patrol at 10:30am Monday for speeding in her black Porsche and failed a sobriety test. She refused to take a breathalyzer and was transferred to the Barstow station where she blew over the legal limit.

Ronson was booked at 2:00pm and charged with DUI.