iTunes not playing thru bluetooth headphones

I have Bose Quiet Comfort35 connected by Bluetooth to a Lenovo Yoga 3Pro running Windows 10 and using iTunes 12.4.3.1. The headphones play sound on all other applications that I have tried and play Windows default sounds. However, iTunes appears to be playing (play button is on, seconds are counting on the display, volume is up), but no sound through the headphones. Is there a setting somewhere in iTunes to address this, or what do I do...?