Brickwalling seems to be the term around here for getting unwanted distortion. Whether that is a correct usage, I don't know. Also, it is never clear whether the distortion is because the SPLs are too high and the mic distorts, or if the external preamp distorts on it input (mic input too hot), or the preamp distorts on its output (preamp trying to send a louder signal than it is designed for, due to gain levels being set too high), or whether the recorder is distorting on its analog input since the signal coming from the preamp is too high, or if the recorder is distorting since you are trying to go above 0dbFS (db Full Scale -- digital 1's and 0's can only be negative or get up to 0 max, beyond that isn't possible and you have clipping).
If you brickwalled -- ie, ended up with a distorted recording -- it could have come from any of the above.
Or even one more option: when I had the OCM R44, one thing I didn't like is that the inner variable gain goes from -infinity (no signal) to max signal, and then the outer stepped ring provided the single gain setting, much like the V3. But if you have the outer gain set too high, and then dial back the inner variable gain, the R44 can distort, but you don't know it since there are no clip meters to tell you it's happening and your levels aren't hitting 0dbFS.
I had this problem once or twice. I forgot now what the solution is. I think it's something like you should never go lower than 12:00 on the inner variable gain setting, and if your levels are too hot and you're clipping (trying to go above 0dbFS), then you should dial back the stepped gain. If you keep the stepped gain where it is and go below a certain point on the variable gain (9:00, 10:00, 11:00?? I don't recall anymore) you can get brickwalling/distortion.