Unlike the Safari, the Equinox is a really high transmit gain detector. The transmit gain cannot be adjusted manually. It was made to hit every target possible from millimeter sized and up depending on your settings and target depth.
So, do you have lots of noise from EMI, from ground mineralization, heavy fertilization, manure or from very trashy ground? You need to find out which it is. Your settings will be determined by this. For instance, in very trashy ground that has lots of small man-made iron and/or aluminum fragments that are from virtually invisible to 1/4 inch iron/can slaw sized you may need to start in Park 1 or Field 1 (Field 1 for sure if there are burnt coal fragments.) Park and Field 1 according to the manual and from my experience will not hit very hard on tiny bits of metal since the multi-frequency weighting is toward the lower frequencies which are not as good for tiny targets. On the other hand, if you have bad mineralization Park and Field 2 maybe better for depth but try lowering your recovery speed one notch and if the mineralization is from iron you might want to use iron bias on at least 1. If you have mineralization from fertilizer you might want to try Beach 1 and carefully ground balance.
Your having to ground balance multiple times sounds like a higher or changing mineralization, fertilizer, manure or burnt coal issue to me. Also, running a detector like the Equinox at the edge of instability on noisy ground is not going to help you get any deeper. It is just going to amplify and smear all of the signals from whatever is causing all of the noise. The Equinox even at 15 sensitivity can go really deep even in badly mineralized dirt on coin sized and bigger targets.
Jeff