The liner drops out of the gripper.

 - If liners are dropped out of the gripper it is most of the times related to alignment.

Make sure that the alignment is done correctly.

- Also be sure that the supplied Air for the actuation is 5.5 BAR. And make sure that the Red and Blue tubings are not leaking at the connections.

If you have an older LINEX version you can change the gripper fingers to a newer type: 

If you have already the newer type, it could be that the Viton parts are no good anymore and you need to replace the fingers.

Part number:  2411-2352  Gripper Finger Right ver. D         
                       2411-2353  Gripper Finger Left ver. D