Bias FX with iPad mini: interface problems

[o_oliviero]

Hello,
first... I am Italian so, please, be patient for my mistakes!
Anyway... I have an old iPad mini and I purchased (maybe 3 yrs ago, I do not clearly remember) Bias Amp and Bias FX from App Store. I wanted to use them with a couple of studio monitors via iRig interface (i mean iRig 1).
Unfortunately, it was impossible to use it because of the amount of larsen effect (impossible to inactivate the inner microphone of iPad...). So I purchased Bias amp 2 and Bias FX pro (now upgraded to Bias FX 2 pro) for PC, via focusrite and connected to a couple of monitors: excellent results and I love it!
But now I would like to use mi Bias FX live using the one I have on iPad mini.
So... I googled for solutions to the problem I described and I’ve found a help page of Positive Grid: they suggest to use iRig 2, Tascam ixz and other stuff.. I purchased Tascam ixz but... same larsen problems as iRig 1!!!

Where am I wrong? Any suggestions?

[Vaultnaemsae]

What is larsen?