Caleb seems to admit he is balding, but still goes out of his way to hide it. As Visual End writes "he's written about going bald in his songs and it's true." He used to have his hair long, which exposed his hairline:
But as his balding progresses he has cut his hair and now combs it forward to hide the hairline:
And the money shot:
It's clear his hairline isn't what it used to be.