Sampling Help - Any way to remove unintented 'phasing/beat frequency' from looped region?

[MusicMayor]

Hello,

Hopefully the experts have some insight/advice they can share and that my explanation below does indeed make sense to someone:

I have a old ~2sec mono brass sample that is looped over the last ~1 sec.
The loop is clean- no clicks, pops, xfade is not required.

When playing this sample back (i.e. via Sforzando), the farther I am away from the root note (higher note), the more obvious the loop is to the user when sustaining a note due to hearing a 'phasing-like beat frequency' effect.

1. Is there any playback SFZ opcode I can add to reduce this audible artifact?
2. Is there any audio VST plugin I can put AFTER Sfz to counter this affect and smooth the frequency variations? It's like I need an anti-LFO effect...



Thanks in advance.