that bounce again

hello i thought that the bounce had been banished long ago,but in my P3d 2.5 it is back with a vengeance when using select vehicle to choose the aircraft it seems unstable floating in the air and bouncing/crashing down to earth or sometime,s the tire,s are buried halfway in the ground,the sim is paused and when the P button is pressed,if it is floating above the ground it crashes onto the runway if the tires are below ground it bounces up and down finally coming to rest on the runway,I believe I have updated to the latest version so any idea what I can do to stop this action,I have previously  used Make runways s but have not installed it in P3d v2.5 does this effect anything to do with the aircraft and runway high

thanks  for reading

peter