Speedo cluster

Hi I have a 97 Honda odyssey and the speedo cluster is stuffing up. The rev needle doesn't move and stays at 0, the odometer had stopped, the engine light goes on and off sometimes, the D light flicks off and on as well. The odometer and rev needle move after I hit a bump but then stops again. I have replaced the speedo cluster but the problems are still there what do you think it is?