The AI-1 is a class compliant device so does not use custom written drivers. It's possible Reaper is trying to use the wrong driver. Does it show up in reaper as the AI-1 driver - it's possible your computer is misreading what is connected.
To check - download Audacity, a recoding DAW that is free. Install it and then see if it also records with the crackling. If it does - then your computer just isn't happy with the Rode interface, which isn't that popular an interface as it's a bit expensive for what it is. Mono interfaces are not really that useful - the first time you go to record a stereo synth or need to use two mics, you will be annoyed.
If Audacity works click free - then it's an internal Reaper issue and I'm not a Reaper expert,