If she's chattering drop the SEN. been useing 1265X for almost 20 or so years got it back in the eighties,a really great machine. The SEN has 2 setting use it in the highest setting to start by pulling the knob out and turning it all the way up when she starts to chatter start turning it back and if you can't stop the chatter rotate back to max and push the knob in and go back to the left till she's stable. To tell you the truth I hardly ever had to push the knob in, 1265 is a rock solid detector. Disc setting Set DISC 1 to about 5( turn DISC up to ripe out a nickel and bring it back to pick it up) Mark it, now you got gold rings, DISC 2 setting is up to you and the trash, usally go to 6-7. it will take pull-tabs, bottle caps nails out real good, can't loose screw cap.
You can also try a low 1-2 on D1 and D2 pick up nickels, low will take out small iron and some foil and leave everything from nickels on up in. Settig works great at fresh beaches.
dig the tabs if there 's not a million, alot of Gold in the 5-7 area and she find Silver no matter what try a 10 sometime no gold but coins come.
Any more help drop me a PM, just had mine redone by Fisher replaced the control housing<plastic was cracked in 3 places, replaced the earphone jack and readjusted all controls Like new.