This model is not capable of firmware updates in the field so no files are available for download. Contact Lectrosonics if you need a firmware update.
IFBT4/E01 v1.5 – 06 January 2025
Added 70, 100, 120, and 150 Hz options to the Low Frequency Rolloff feature.
IFBT4/E01 v1.0 – 18 May 2009
First production release.