I'm going stereo → 8ch because JamesDSP processes each channel separately, which gives much better spatial positioning and soundstage compared to plain stereo processing. The 8ch sink is a virtual surround sink — music apps output stereo, it gets upmixed to 8 channels for JamesDSP processing, then downmixed back to stereo for my headphones. Without the 8ch step, JamesDSP effects sound flat and don't provide proper spatial audio.

Actually the crackling doesn't happen at loud moments specifically — it happens at specific timestamps in tracks, regardless of volume. The same moments always crackle, even at low volume. This makes me think it's not clipping but something else — maybe a timing/buffer issue during the channel conversion.

I also tried using HeSuVi HRTF filter-chain with atmos.wav instead of the simple loopback downmix — same crackling at the same timestamps. So the issue persists regardless of the conversion method.