Kanye West -- Rough Ride at Hollywood Bowl (VIDEO)

Kanye got a refresher course in the value of rehearsals Friday night at the Hollywood Bowl, when things didn't go according to plan.

Kanye kicked off the first of a 2-night stand at the famed venue, where he performed all his songs from "808's and Heartbreak."

The first half of the show was flawless, but the Gremlins burrowed their way in as the show went on. The tracks were out of sync with Kanye, and at one point (see video) Kanye orders the music to stop.

We're told Kim's hubby was late for rehearsal Thursday and because of noise restrictions, when he finally arrived they sent him home.

Kanye made a passing reference to the problem, when he said Friday night, "This is the best dress rehearsal I've ever had."