When using the TimeFactor as part of a recording setup, it's best to set the I/O to Line Level and use balanced connectors. This Marian interface does not use standard +4 dBu, -10 dBV I/O settings so it will take some experimentation to get levels going into the TimeFactor set correctly. I would start out at +8 dBu and make sure that you're not distorting the input of the pedal and input of the interface when returning the signal. Basically, when you're sending signal from your DAW and it's peaking around -6 DBFS or so, you should hear the signal coming back from the TimeFactor without distortion. If it's too hot, -6 dBV on the Marian might be the way to go. In that case, switching the TimeFactor to "Gtr level" might work better to more closely match the voltage. In either case, pay attention to the noise floor during quieter sounds to ensure it's not too loud – a clear indication it's the wrong setting.