When I connect my Ditto Looper to my amp everything is fine, but when I connect it to my mixer, there is a big volume jump when I engage the pedal. Also, connecting to my amp, my electric guitar is fine, but I get a similar volume jump when using my acoustic guitar.
This is due to an impedance mismatch.
The way to avoid this is to use a buffer either before or after the Ditto.
All of our TonePrint series pedals have buffered as well as true bypass modes. There are also companies who make simple buffer only boxes. Please see your retailer for more details.