I took it back out the last 2 days. I did actually get a couple good things...my oldest coin, an 1883 Indian head penny, and the back of a 2 piece general service button which even though just the back...is my first Civil War button. But...the penny rang up mid 90's and was very scratchy and the penny was only about 4" deep. Nothing else in the hole. I almost didn't dig it. Rest of the time that day and yesterday...no solid targets, almost everything is scratchy regardless of depth and most of them seem to want to ring up in the 90's regardless of what they are.
So yeah:
-Broken coil or machine seems likely
-I checked connections so I don't think incorrect assembly is the issue
-Don't think it's EMI. No overhead or underground power. Not near any radio towers. Even left my cellphone in my Jeep this time because I read some people say it can cause issues. Doesn't seem to matter if I leave it or have it in my pocket...acts the same. My AT Pro is not affected at all at these same locations.
-2.77. Mostly Park 1, sometimes field. Ground balanced. Sensitivity is 2 notches from top. Not sure if there's anything else I can or should do to set it up properly.