on Flex machines, Buffers are and can be assigned to Slot numbers for this purpose. You can place a trig replaying what the buffer has just as any sample in the flex slot list and if you “slide” thru that samples starting point your sample can feel like become granular. In example by using Playback-Pages params STRT, LEN, RTRG, RTIM and likewise on top using ATK, HOLD of the Amp-Page. Just be aware once the virtual playhead is behind the loop point the sample needs restart to scrub again… So your loop settings are of interest as well and therefore the length of your recording is also not without meaning.
As soon the length of a recording is known or can be assumed to be known, then the playhead has something to relate to and can certainly scrub thru it in the precision 64 of 64 chunks/slices or the fixed multiple of the time domain offered by its relation to tempo, depends on your chosen options for that flex machine on track.
• STRT, where to start playing
• LEN, how long can it play if available
• RTRG, how often does it repeat
• RTIM, in the loop frame size above 0.005x and below 8.0x (of the entire sample length i think)
So the goal is first to feed your buffer, seems you figured that out already.
And a buffer is just as good as any sample, even if not saved.
You can not scrub thru something that is not cached in the buffer.
there are other tricks as well. In example using endless FX2-Delay controlled by a trigless trig or scenes and apply the maximum feedback FB & SEND at the moments you want it and time TIME becomes the loop length . As you feed the delay buffer you practically just repeat, can sound granular even tho it is not granular at all.