I've used a GTI 2500 for several years. I, usually, hunt in coin mode as I haven't figured out how to get stability in all metal mode. I would like to hunt in all metal, sometimes, but I can't seem to master a stable tone. It just seems to go wild. I used to hunt with the ADS detectors that had an automatic mode in all metal with great stability. What suggestions can other 2500 users give to me to help with the stability?? All help would be appreciated.