It happens for me with almost any preset that has a HP Filter FX on both layer A and B ... I can safely say, that this bug has not been fixed, I can reproduce it quite easily, and yes it has been reported as fixed some times... even though Sequential has stated that this bug has nothing to do with the FX engine, it just seems to happen when the FX type is the same on both layers... I've witnessed it only with HP filter and Distortion, but I think that the fix they are talking about is related to using two distortion FX... because I've not witnessed any bug by using two of these since they fixed it... but two HP filters is another case, and it definitely introduce the sample-reduction like sound...