I have this issue on my Garrett AT Max as well. I bought it 3 years ago and it was fine the first year but from the 2nd year to now it's gotten exponentially worse. I also feel that it has gotten worse depth and that it's confusing non-ferrous for ferrous. A few days ago it supposedly found iron and purely by chance I dug it because it was a new place so I wanted to check the ground out and it was a coin, but the signal and noise was telling me it was iron junk... I tested today with a bit of aluminium foil I found and it couldn't find it in a 20cm hole with dirt on it... I expect better.
@Kamil Just in case you were curious or someone else comes across this in the future with a similar problem: I opened mine up and... the connector on the circuit board for the coil connector cables was broken, literally all 6 solders were loose and came off, and the gold conductor lines were stuck to the solder on the 6 pins that came off the board with the connector so I assume this is an unfixable thing. The day after I posted my original comment the machine started making noise when I touched the control box, and when I came home I didn't even have to touch the control box, swinging my hand above it would make it detect iron and touching the coil connector as light as a feather made the machine go crazy, that's what made me finally open it up coupled with a bad hunt because it barely could detect anything. Honestly I think I'm done with Garrett and will buy a different brand, probably Minelab. I've read many threads lately and there are a few problems that seem to be super common, something Garrett should have fixed many years ago. The button issue being one, another being the nut that holds the coil connector in place spinning around when tightening/loosening the coil connector, both of those was a problem for me and now this out of nowhere. The ground solder was also very shoddy inside the machine. Their customer support may be good, but that doesn't excuse continuing to produce products with known issues for several years and not fixing them. I've been taking very good care of my machine so it puzzles me that this happened to it, I really don't understand how it can have happened other than bad production of the circuit board.
I have this issue on my Garrett AT Max as well. I bought it 3 years ago and it was fine the first year but from the 2nd year to now it's gotten exponentially worse.
I also feel that it has gotten worse depth and that it's confusing non-ferrous for ferrous. A few days ago it supposedly found iron and purely by chance I dug it because it was a new place so I wanted to check the ground out and it was a coin, but the signal and noise was telling me it was iron junk...
I tested today with a bit of aluminium foil I found and it couldn't find it in a 20cm hole with dirt on it... I expect better.
@Kamil Just in case you were curious or someone else comes across this in the future with a similar problem:
I opened mine up and... the connector on the circuit board for the coil connector cables was broken, literally all 6 solders were loose and came off, and the gold conductor lines were stuck to the solder on the 6 pins that came off the board with the connector so I assume this is an unfixable thing.
The day after I posted my original comment the machine started making noise when I touched the control box, and when I came home I didn't even have to touch the control box, swinging my hand above it would make it detect iron and touching the coil connector as light as a feather made the machine go crazy, that's what made me finally open it up coupled with a bad hunt because it barely could detect anything.
Honestly I think I'm done with Garrett and will buy a different brand, probably Minelab. I've read many threads lately and there are a few problems that seem to be super common, something Garrett should have fixed many years ago. The button issue being one, another being the nut that holds the coil connector in place spinning around when tightening/loosening the coil connector, both of those was a problem for me and now this out of nowhere.
The ground solder was also very shoddy inside the machine.
Their customer support may be good, but that doesn't excuse continuing to produce products with known issues for several years and not fixing them.
I've been taking very good care of my machine so it puzzles me that this happened to it, I really don't understand how it can have happened other than bad production of the circuit board.