Mono Mix Modes Don't Work

I have a stereo sample with distortion in the left channel. I would like to mix the sample to mono by keeping only the right channel, but no matter which mix mode I choose (Keep L, Keep R, Mix) I only ever get the left channel.

Is this a bug or am I doing something wrong?

Everything seems to be working fine here in Renoise 2.1, both when using the sample editor’s adjust properties function, or when using the stereo expander device to reduce (un-expand?) a track to mono.

is the distortion really in the sample, or is it introduced by some dsp effect in the channels effect chain which is peaking/distorting?