Daniel, we retested the SRV / Pride and Joy shuffle cursor issue against alphaTab 1.8.3 after #2702.

Bug is still here but much worse!

alphaTab 1.8.3 appears to degrade native cursor motion globally:
cursor no longer glides smoothly and instead steps/hops note-to-note across playback in addition to parking on the first beat slide in M1. Prior to this on the same It'sMyTabs LouisLam repo the player showed the cursor doing a slingshot in which it would jump twice. But the logs do not pick up the cursor parking:

Original Baseline Testing Prior to the V1.8.3 Version Update:

What the 1.8.1 baseline proves

1. Native timing is monotonic during the visible jumps

Both regression objects show:

timeDelta: +2.666ms
currentTickDelta: +1
isSeek: false
currentTickMovedBackwardWhileTimeForward: false

So alphaTab’s playback clock is not moving backward during the observed slingshot.

2. The native cursor X jumps sharply forward

First jump:

currentTick: 613
nativeBeatX: 122.752 → 164.617
nativeBeatXDelta: +41.865
nativeCursorSharpMoveWhileTimeForward: true

Second jump:

currentTick: 1449
nativeBeatX: 156.831 → 214.569
nativeBeatXDelta: +57.738
nativeCursorSharpMoveWhileTimeForward: true

visual observation: the native cursor races/slingshots forward.

https://youtu.be/HqJOu57SDp4

After V1.8.3 installed:

The issue still reproduces in a native alphaTab testbed, without Maestro’s custom cursor involved.

Environment:

• Testbed: LouisLam / ItsMyTabs native alphaTab player
• Browser: Chrome on macOS
• Packages:
  • @coderline/alphatab: 1.8.3
  • @coderline/alphatab-vite: 1.8.3
• Playback speed: slow practice speed, same as previous 1.8.1 baseline
• Song/passage: SRV / Pride and Joy, opening shuffle / slide region
• Probe: read-only DevTools probe watching playerPositionChanged, activeBeatsChanged, currentTick, and native .at-cursor-beat transform X

1.8.1 baseline:

• eventCount: 1496
• regressionCount: 2
• currentTick and currentTime were monotonic during both visible jumps
• native cursor X jumped sharply:
  • tick 612 → 613, X 122.752 → 164.617, delta +41.865
  • tick 1448 → 1449, X 156.831 → 214.569, delta +57.738
• currentTickMovedBackwardWhileTimeForward stayed false
• nativeCursorSharpMoveWhileTimeForward was true

1.8.3 comparison:

• eventCount: 1584
• regressionCount: 2
• activeBeatsChanged attached, but active beat identity remains coarse:
  • primaryBeatAbsStart: 0
  • primaryBeatPlaybackStart: 0
  • primaryBeatPlaybackDuration: 3840
  • primaryBeatDuration: 1
  • primaryBeatNotesCount: 0
• The visual failure changed shape:
  • tick ~607: native cursor X = 122.752
  • tick ~642: native cursor X = 155.824
  • tick ~1444: native cursor X is still 155.824
• Visually, this appears as the native cursor parking/holding on the slide/shuffle region before the later transition.

Conclusion:
#2702 changed the behavior, but did not resolve the issue.

In 1.8.1, native alphaTab cursor behavior showed discrete sharp forward jumps in SRV/Pride and Joy shuffle playback.

In 1.8.3, the issue is worse: the native cursor appears to park/hop from anchor to anchor across playback. currentTime and currentTick remain monotonic, but native cursor X stays frozen over many ticks and then jumps to a new visual anchor.

This suggests the remaining bug is not playback clock reversal. It is native cursor visual-anchor lookup/interpolation in swung/shuffle passages.

Additional 1.8.3 evidence:

A longer 1.8.3 run through the opening M1 region produced: (As was just captured in the video evidence that was just recorded)

• eventCount: 19292
• sampleCount: 19292
• regressionCount: 81
• activeBeatsAttached: true
• activeBeatsEventCount: 104

This is materially worse than the 1.8.1 baseline, which produced only 2 native cursor sharp-move regressions.

Observed behavior:

• The native cursor no longer glides smoothly.
• It parks/holds on discrete X anchors while currentTime/currentTick continue forward.
• It then hops to later note/anchor positions.
• Video confirms visible note-to-note stepping throughout playback.

Probe pattern:

• currentTime advances normally
• currentTick advances normally
• isSeek is false during playback samples
• nativeBeatXParsed remains frozen across many samples
• then jumps to a new X anchor

activeBeatsChanged also appears too coarse for this passage:

• activeBeatSamples repeatedly report primaryBeatAbsStart values like 0, 3840, 7680, 11520
• primaryBeatPlaybackStart remains 0
• primaryBeatDuration remains 1
• primaryBeatNotesCount remains 0

Further Conclusion:
The 1.8.3 swing lookup patch appears to have changed the failure mode from sharp cursor jumps to widespread cursor parking/note-hopping. The issue remains native alphaTab cursor visual-anchor lookup/interpolation, not Maestro custom cursor logic.

Will Attach YouTube video here: Or with the compact

Originally posted by @AvaTheArchitect in #2702 (comment)