Headphones = drums and ipod : Monitor only plays drum audio

[Zerk71]

Hello - I am new here, and I tried searching for this, so I hope I am not duplicating a thread.
I just bought a used TD-20 with a KC-550 amp. When seller demo'd it for me I plugged my iphone into the Mix In input and played along with a song hearing both the music and my drumming. When I got home, both music and drum audio come through in the headphones, but only the drums come through the amp. I have plugged the phone straight into the mono input on the amp and the audio comes through then so I am not sure if I somehow missed a setting on the TD 20 to allow the audio to pass through? Any help/suggestions are appreciated!

Dave

[BarT]

Check at SETUP, OUTPUT, OTHER whether MIXIN is routed to MASTER. (You can restore defaults there by pushing F5 a couple of times.)

Bruce