MixDesk X 1.42.021 — fix: distorted output on some USB DACs (macOS)

MixDesk X 1.42.021 — fix: distorted/quiet output on some USB DACs (macOS)

If a specific output device sounded quiet, distorted, or triggered constant
crackle warnings in MixDesk X — while the same device was perfectly fine as a
direct system output — this release is for you.

The special case, explained

Some USB DACs advertise 16-bit modes alongside their 32-bit/float modes.
On macOS, the audio backend MixDesk X uses (miniaudio) prefers 16-bit
internally on such devices — and its format converter then pulls audio frames
at exactly double speed. MixDesk X's buffers were drained twice as fast as
they were filled: every second block was garbage. The result was quiet,
distorted output and a permanently firing crackle detector, while the same DAC
played flawlessly when addressed directly by macOS (which does its own, correct
conversion).

Devices that only expose float formats — most audio interfaces, and the
virtual driver — never hit this code path, which is why the problem seemed to
follow one particular device around.

The fix

MixDesk X now opens playback devices in their native 32-bit integer format
whenever they offer one, and performs the sample conversion itself. The broken
converter is never in the signal path anymore. Float-native devices keep the
existing direct path, and Windows is untouched (WASAPI conversion was always
correct).

Verified on the DAC that uncovered the bug: bit-transparent playback, no
crackle, and the device finally sounds like it does when driven directly.

Files

• MixDesk-X-1.42.021.dmg — macOS (Apple Silicon, notarized)
• MixDesk-X-1.42.021-arm64-installer.exe / MixDesk-X-1.42.021-amd64-installer.exe — Windows