Can anyone help? Three times this past weekend I've gone to open the roof, windows drop, roof opens, top cover raises normally, roof goes back as it should but then top cover lowers slowly as if its not under hydraulic pressure but falling under its own weight, it gets to about 3" from closing and the cycle stops. On two occasions I've released the roof button momentarily and tried again and it's worked, the roof top cover locks, however on one occasion it didn't and I had to reset the roof by closing manually. anyone else had this problem? All comments appreciated! Cheers!