I retrieved this from the old AOR UK website before it disappeared:
"AR3000A INTERMITTENT OR OPEN SQUELCH
If the receiver squelch becomes intermittently OPEN regardless of squelch control position and changes with mechanical movement of temperature, the unit may be suffering from a cracked surface mount component on the i.f. PCB.
Have a look at the solder side of the PCB (the i.f. PCB is the bottom board), you will need to temporarily remove it from the radio.
Look on the opposite side of the board to the ceramic resonator marked CF2 (usually orange in colour). There are usually two added conventional components, one being a resistor (12k) and the other a disk ceramic capacitor (possibly green in colour) with a value of 102 (1000pF).
The capacitor is attached to a 3-pin device at one end and is soldered between a SMD resistor and SMD capacitor at the other... the capacitor may be cracked ??
Temporarily lift one leg of the disk capacitor and see if the SMD capacitor falls in two !
Replace the SMD cap (size is 0805), the value is 103 (C170)... in 'real language' this is 0.01uF or may be expressed as 10nF.
One one occasion, it has been reported that another SMD capacitor C82 (103 / 0.01uF / 10nF) was also faulty resulting in confusing squelch problems, this capacitor is situated just one component away from C170, only R190 separates the two components.
Re-build and test."
They went on to give a pdf file showing a closeup of component locations which I also have. PM me if you'd like this.
It might also be worth downloading the AR3000a service manual from mods.dk, and poking around the AGC or NFM mute stages to see what is going on. If the AGC is common to both AM and NFM, you might want to check its action on AM shortwave... if it sounds like the AGC is really slow to react, then this might be your problem.
