This document is a spec for a set of new UGens for SuperCollider that will allow for arbitrary sub-sample indexing into audio buffers up to 2139095040 samples long (12.3 hours at 48k).
Work-in-progress implementation of this spec can be found here.
BufRd currently accepts a 32-bit float as an index into a buffer. This is due to limitations of SuperCollider’s server architecture. This means, using BufRd to play an audio buffer at a playback rate of 0.3, I start noticing major artifacts around 2**20
samples in (20 seconds at 48k):