Release Candidate 4.5.9 Hotfix — Faster Feedback, Same Detail

Release Candidate 4.5.9 Hotfix — Faster Feedback, Same Detail

Rapid feedback should stay responsive, not build up a delay during sustained action. This hotfix targets the DualSense Bluetooth feedback backlog reported in #81 while retaining the RC4.5.8 haptics and disconnect fixes.

What's improved

• Faster native feedback dispatch: game feedback now has a separate 500 Hz / 2 ms software pacing ceiling instead of sharing the 200 Hz / 5 ms local-settings cadence. Distinct effects and stops remain ordered; audio and microphone scheduling retain their existing boundaries.
• No unnecessary repeat backlog: consecutive byte-identical, known state-setting commands may share an unclaimed pending queue entry. Changed effects, A-to-B-to-A transitions, stops, unknown commands, extra trigger bytes, and ownership changes are preserved.
• Adaptive-trigger commands use the faster path too. Automated tests verify trigger changes, complete trigger payloads, and release commands remain intact. Live validation covered body rumble, not in-game adaptive triggers; this addresses the shared queue-delay cause, not every possible cause of trigger skipping.

This is not a gain boost or a rollback. PCM samples, codec settings, audio cadence, native rumble-mode ownership, per-trigger Trigger Lab priority, and Nintendo HD-rumble tuning are unchanged. Existing Switch 2 and Joy-Con functionality remains included.

Measured on a Bluetooth DualSense

In a controlled one-second 250 Hz body-rumble burst, all 251 changes, including the final stop, reached the physical Bluetooth writer in order. Against RC4.5.8, the final-stop submission delay fell from 252 ms to about 0.18 ms. Two additional candidate runs preserved all 251 changes, with final-stop submission delays of 0.15–0.18 ms.

These are host-side source-write-to-physical-writer measurements, not radio acknowledgments, actuator latency, guaranteed 500 Hz hardware throughput, or proof of every game's behavior. GTA rapid-fire gameplay and adaptive-trigger feel still need in-game confirmation. Short input checks showed no consistent report-interval worsening during these bounded bursts.

Downloads

• Installer: DS4Windows_5.0.5.9_Setup_x64.exe
• Portable: DS4Windows_VIIPER_x64.zip — extract the entire ZIP, not just the EXE.

Both include the complete, unchanged VIIPER 0.1.4-rc4.5.6 package and Xbox output identity. No new broker release is required. DS4Updater 2.0.6 remains compatible; the portable bootstrap obtains the published updater rather than bundling an outdated copy. Close DS4Windows and VIIPER before replacing files, and keep your profiles.

Validation

The rebuilt x64 suite passed 5,539 tests with zero failures and 11 existing hardware/environment-gated skips. Allocation assertions remained enabled, including a new intentional-allocation control. Coverage includes ordered native feedback, trigger payload preservation, media/PCM continuity, transport retry and completion handling, and existing Nintendo behavior.

Published as an unsigned release candidate under the existing draft-first VIIPERRC policy. Matching sources, notices, checksums, and the GitHub Actions build record accompany the downloads. Detailed evidence is recorded in the feedback cadence validation.