I have a two-channel amp which allows me to switch between clean and and overdrive sounds. When I place the Ditto Looper in front of the amp and record a loop, the sound of the loop changes when I switch channels. Why is this happening?
This happens because the looper is placed before the amp, and because you are not using any overdrive/distortion pedals to change between your clean and dirty sounds BEFORE the Ditto, the overdrive sounds are of course placed after the Ditto in the signal chain.
What this means is that your guitar sound is clean when it passes through the Ditto Looper and does not get distorted until it hits the amp. This would explain why the recorded loops change sound when you change to your lead sound - the looper has recorded a clean sounding guitar which is then sent to the amp where it gets distorted.