Help with a garrett meter.

[Plug popper]

Hi all. I have a Garrett master hunter 5 that the meter works' but is kind stingy or slow. Like i said it works but seem's to be slow and dose not read just right. If you run a dime under it it reads just under a dime same with a penny as well. The meter dose not respond as fast as my other units. This unit works very good other than that. Any help would be nice. Thanks

[dtpost]

Do you shake it when that happens, was thinking a loose wire.