From that recording it's hard to tell what's being caused by the speakers and what's being caused by the phone recording and doing it's noise-reduction thing (i

From that recording it's hard to tell what's being caused by the speakers and what's being caused by the phone recording and doing it's noise-reduction thing (it sounds like it's recorded with a phone). Can you record the main output of the mixer into a DAW instead and post the MP3 of that? What model of mixer is causing the problem?