How to Fix Unity Music Crossfade Comb Filtering From Phase Cancellation

Comb filtering happens when two near-identical signals overlap out of phase. Aligning them, shortening the overlap, or choosing distinct material removes the hollow phasing during the transition.

How to fix it

1. Sample-align the tracks

If both tracks come from the same arrangement, start the incoming track at the exact same sample position as the outgoing one so their phases match during the overlap.

2. Use an equal-power crossfade

Fade with an equal-power (square-root) curve instead of linear so the combined loudness stays constant and the overlap window where cancellation occurs is minimized.

3. Shorten the overlap

Reduce crossfade duration to a beat or two. A long overlap of similar material maximizes the time available for comb filtering; a short one is far less audible.

Catching the ones you can't reproduce

The hardest version of this to fix is the one you can't reproduce — it only happens on a player's hardware, OS, driver, or save state, under conditions that simply aren't present on your machine. A report that says “it crashed” or “it froze” gives you nothing to act on, so the bug survives release after release while quietly costing you players.

Automatic error capture closes that gap. Each failure arrives with its full stack trace, the device and OS, the build number, and a breadcrumb trail of what the player did right before it broke, so even a failure you have never seen becomes a specific, reproducible issue. Fold identical failures into one signature ranked by how many players each hits, and your worklist sorts itself worst-first instead of arriving as a stream of vague complaints.

This is where a tool like Bugnet earns its place. Its SDK captures every Unity error automatically with the full stack trace plus device, OS, memory, build, and game-state context, folds duplicates into one grouped issue with an occurrence count, and ties each to the build it first appeared on — so you fix the problem that hurts the most players first and confirm it is gone when its signature disappears from the next release.