Here are the likely culprits:

Dither settings: If the project is at a higher bit depth (e.g. 32-bit float or 24-bit) but they’re exporting to 16-bit without controlling dithering, the DAW may be auto-applying dithering. This often introduces faint noise, which is intentional but can sound strange if not expected.

Export settings mismatch: If the DAW is working internally at 48kHz/32-bit float but the render is set to 44.1kHz/16-bit, the conversion process can add artifacts or noise if not handled with proper settings.

Plugins on the master bus: Some plugins (especially limiters, tape/vinyl emulators, or noise-generating effects) only print their “subtle noise floor” on render, not during real-time playback, depending on how oversampling or quality modes are set.

Normalizing or auto-gain: If export has “normalize” or auto-gain enabled, it could bring up the noise floor and make it audible.

👉 To check if it’s a sample rate/bit depth mismatch specifically:

Export at the same sample rate/bit depth as the project (e.g., 48kHz 24-bit).

Export with dithering off, then with dithering on, and compare.

Render to WAV first at full quality, then encode to MP3 separately using a dedicated encoder to see if it’s the MP3 conversion adding noise.

• This post was modified 3 weeks, 4 days ago by Alan Cox.
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