I get it too sometimes. Mostly on the ears for my drummer where the kick is up 6 db with a hot gain.
It happens because the Ilive runs a fixed point (24 – I think) bit structure. When you run out of bits it overloads. If you pull down your entire mix it goes away.
32 bit floating point (digico) does not overload as it uses 8 bit to define zero for the next 24 bits. This is one of the very few drawbacks of the Ilive design. A&H have chosen the fixed point DSP farms for their accuracy and features with they have valued higher then this relatively small issue (as I understand it)