Zoom U 44, stereo input from effect pedal but mono output from headphone jack
I apologise in advance for the slightly off-topic question but that's the only audio-related forum I am currently subscribed to, besides, I read some discussions about the Zoom audio interfaces in the past so I assume there are some Zoom users among us.
Here's my question:
I've got a hardware synth which I connect through a stereo reverb pedal to my Zoom U 44, using two mono 1.8" jack cables to inputs 1 and 2. Everything is working well so far, and I managed to record audio to my DAW (still have to try the iPad connection, but I assume there shouldn't be any problem there too).
The problem is, when I monitor the output of my synth through my Zoom headphone jack,, what I get is a kind of muddy signal which appears to be a monophonic blend of channel 1 and 2 input. It sounds so bad! I almost returned my reverb pedal thinking it was a defective unit! But then I tried listening through my Mac headphone jack, while monitoring the audio through the Zoom connected to my Mac via USB, and my it sounds like heaven! Full stereo goodness!
So what did I do wrong? Why is the headphone output from my U-44 not conveying the proper stereo signal?
Thanks in advance for any insight!