Reviewed 11/10/2020
NOTE: Firmware for all Series III products can now be downloaded directly from PreSonus.com without registering.
You can download the firmware for your respected Series III device via its product page, and then click the Downloads tab. Be sure you download the firmware for your specific Series III Product as the firmware is not interchangeable between Series III devices.
As an example,
Here is the download section for the StudioLive 64S:
https://www.presonus.com/products/StudioLive-64S/downloads
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