If some of you guys mean that the detector goes berserk for five or ten seconds and then quiets down, that is perfectly normal.
It happens with all detectors that run hot. It's a common occurrence with the T2, Gold Bug Pro and Blisstool among others.
Don't worry about it. Just put the coil on the ground and wait for it to stop. I'm surprised the manual doesn't mention this because it would save people a lot of concern.
If the noise is continuous it could be EMI. Electrical interference is stronger at different times of the day so a place might be noisy one day and quiet the next.
Concerning the Garrett Pro Pointer. If you like to run high sensitivities, it can't be carried anywhere in front of your body without the T2 picking it up. Strangely, this only happens when the Pro Pointer is turned OFF. Turn it on and there is no problem. To deal with this I made an aluminum foil sheath to carry the Pro Pointer in. The foil prevents the T2 from picking it up. I covered the foil with duct tape on both sides first, then rolled it into a sheath and it works great.
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