It sound HOT! is this also in full sun?
Solar energy can mess with detectors a good bit especially if your running higher more sensitive setting (Hot Setting)
You didn't mention what settings your running?
Remember, you can only run the setting as high as you can control the detector.
Different conditions will demand different settings.
Try, a minus -3 on the threshold & maybe a 70 on the sensitivity.
Your max setting will be the point where you have a hint of chatter but good audio reports on targets.
In some areas where there is a LOT of interference sometimes a smaller coil will help, smaller means a smaller antenna.
Try the same area say in the morning before its so hot and see if that helps.
On many occasions I've started out in the morning with really HOT setting to find that by Noon, I had to back them off some.
You can't always run +2 Threshold & 90 sensitivity. The ground in the very early morning has less solar charge which less effects the detector.
Some here will argue that point I'm sure, but years ago I used to Night Hunt, I could run WIDE OPEN settings! it really help if the ground is just a tad damp.
I've been out hunting on really hot full sunny days and I've lost total control of the detector, I had to pack it up and go home.