I found a baby boat billed flycatcher bird?

it is a baby boat billed flycatcher that i found outside being barked at by dogs inside a gate. the thing was shivering, and had a few scratches. i put it in a box inside by a window with ripped up paper towels. i soaked bread and every so often would feed it to him. over night he was fine. we found out he has mites so we are getting mite drops also. my problem is that he wont stop squeaking: every 5 seconds :P what is this, and how do i make him stop?