You guys may be right on the Angels cap, but it's definitely a White Sox logo that shows faintly in the photo. It's a little more visible in this one (which I should have posted before but just got around to scanning).
Pretty sure it matches the home uniform logo from 1931 (shown below). I'm not sure what to make of the single/double piping discrepency though. The only other possiblity would be the 1929 White Sox home uniform, but that makes less sense given Lew was in the middle of his stint with the Indians at that time. Any earlier than that, and Burke wouldn't have been photographing ballplayers yet. Looks like the White Sox did their spring training at League Park in San Antonio, TX from 1930-32, if that helps?
1931
1929
