issue with pulsating ambient strings clips please advice?

[InaBalloon]

Issue with pulsating strings, when imported into a session clip.
Tried warping on and off different warp textures/tones, no difference, while the original take sounds clear, and not pulsating.

Also tried to make the clip 8 bars in stead of 32 bars, no result other than the same pulses.

Anyone familiar? solutions?

The sound needs to be looped, but with loop off, no difference.

Laurens