Ok got my zoom g3 and i hooked it up to my amp and lot of the effects are causing major unwanted feedback, the delays are way too over the top and lowering the settings, i dont have fx loop either, any ideas?
Make sure in the settings you have the type of connection correct.
Under Global Settings, the left pedal knob #3 adjusts this. Choices are:
Direct - For headphones or monitors
Combo Front - Using a guitar input of a combo amp
Stack Front - Using a guitar input of a head amp
Combo Power Amp - Using an effects loop return on a combo
Stack Power Amp - Using an effects loop return on a head
Sounds like yours should be set to Combo Front.
Also, on that same left pedal, knob #1 adjusts the global overall volume. Make sure that's not too high.