Who called from 5123548932

Been getting calls from this number usually in the early morning ( 6am - 630am)  Never leave a message.  Isn't kind of early for these calls?

Weird times of the day. no one at the other end

just got a call from this number saying they are IRS and I know that they do not call after 7 o'clock at night.

9:30 PM Eastern.  Called it back, disconnected number.  No processing center in Houston.

Just received 2 back-to-back calls from this number, no message left.  Appears to be from Austin, TX., says IRS on caller ID but no reason for TX IRS office to call a resident of a different state that has its own IRS office! Weird ...