I would add a potentiometer with the signal input at one end, ground at the other and the wiper connected to the 22 k ohm resistors . This allows you to control the amplitude. If the pot is unnecessary, you'll find out if you have to turn it all the way up to get the chip to work and you
will not risk blowing the chip. The pot would replace the 10:1 voltage divider. You can try a pot
on one input only to test it. More than likely the 22 k ohm resistors are "dropping resistors" to
limit the input current and the chip schematic assumes a standard LINE LEVEL signal, and the pots are not necessary. (all cell phones have headphone volume controls anyway)