Hi everyone,I recently sent my f75 ltd that I have had for 5 years in for the upgrade mainly for the dst around electric fences and other emi. Anyway,I got it back Friday and went to my test garden. I mainly ran my old machine in all metal but occasionally in disc mode. Ok,i started with the factory 11'' coil in my garden in 9.0 and all metal,boost process, sens 98 and it gb'd around 60 and you couldn't even hear a .58 cal minie ball buried at 8" so I went to the 6" minie ball and you could barely hear it and vdi was showing iron,next I went to the 3" minie ball and it sounded like it should but the vdi numbers were all jumping from 8-22. I then switched to disc with sensitivity 95,2F,boost process and it basically had the same results. Tried the same tests in 9.1 and had the same results. So,i then switched coil to my round 5'' coil and did the exact same tests and in all metal you couldn't hear the 8" minie ball but at 6" and 3" it was loud and gave steady numbers of 45-55. In disc mode you could hear the 8" minie ball an pretty good numbers. This is so strange because with my old detector using the 5" coil you could hear the minie ball at 8" and the numbers were jumpy but it would jump up in the 45-55 range and in disc mode it wouldn't hit it. A couple questions,does it sound like my coil was somehow damaged or does it sound like ive got a lemon? Are you guys seeing better depth in disc than all metal? Does Fisher not test the machine after they upgrade it? Something is definitely not right with mine. Its so bad with the 11'' coil that I had to but a .58 cal minie ball an inch from the coil to get a solid reading of 50-55. Any help will be greatly appreciated