"Erosion" mostly makes me think of bit reduction/crushing and other audio degradation stuff. The Data Bender is the big one here, but you said you didn't like the sound of the "Qu Bit" (the company that makes Data Bender) so I'm assuming that's what you meant.
The aforementioned FX Aid could do the trick. It has several degradation/lo-fi algos (like Shallow Water, LoFi Junky, etc.), and it and you can apply voltage to its SRR input to reduce its clock and get bit reduction on top of that.
Other possible modules would be the VoicAs ReduXer, or maybe something like the Befaco Crush Delay. You can technically patch your own bit reducer with a S&H and superfast clock/audio rate triggering. Another option are various rectifiers, saturators and distortion units, but that possibly sounds more aggressive than what you want.