No sound from Apogee Jam with iPad mini and Lightning-30 pin adapter

Hello everybody.

I'm trying to use my Apogee Jam with iPad mini but I am unable to hear any sound from it. Jam seems to work, since the led become green and react to the guitar signal. I tried two different guitars and different cables but nothing changes. Jam also works perfectly on MacBook Pro and garage Band, so I first assumed the issue was in the iPad or in the Lightning-30 pin adapter (genuine).

Oddly on AmpliTube I can tune the guitar, so some signal arrives to the iPad, but I can't do the same on JamUp, where the tuner seems not to reiceve any signal. Are there some settings I should check on the apps?

Thanks for any suggestions!