https://www.fractalaudio.com/downlo...xe-fx-3/19p0/axefxiii_dsp_rel_19p00_beta3.zip
Fixes the Megatap bug plus a few other little things.
19.00
Version 19.00 firmware represents the first use of the Chase Nonlinear Feedback (CNFB) technique for the solution of nonlinear ODEs. The power amp algorithm has been completely rewritten using the CNFB method. This provides improved accuracy, especially in the clipping and power supply sag behavior vs. frequency.
Added y-axis labels to RTA.
Added Time Shape parameter to Megatap Delay. The EXP/LOG setting is the default and behaves as before allowing time shapes between exponential and logarithmic (including linear). The SIGMOID setting is a four-quadrant shape that allows time shapes between sigmoid and inverse sigmoid. The COSINE and SINE settings select sine wave shapes with the Time Alpha parameter controlling the number of periods from 1 to 8.
FC: Amp Level Save now has an option for 0 dB to allow saving a preset via a footswitch.
Fixed signal level into power amp a bit too high in 6160 models.
Fixed Compressor block Auto-Gain not being updated when changing types.
Fixed wrong op-amp clip threshold for DS1 models in Drive block.
Various other fixes and improvements.
Fixes the Megatap bug plus a few other little things.
Axe-Fx III Firmware Release Notes
19.00
Version 19.00 firmware represents the first use of the Chase Nonlinear Feedback (CNFB) technique for the solution of nonlinear ODEs. The power amp algorithm has been completely rewritten using the CNFB method. This provides improved accuracy, especially in the clipping and power supply sag behavior vs. frequency.
Added y-axis labels to RTA.
Added Time Shape parameter to Megatap Delay. The EXP/LOG setting is the default and behaves as before allowing time shapes between exponential and logarithmic (including linear). The SIGMOID setting is a four-quadrant shape that allows time shapes between sigmoid and inverse sigmoid. The COSINE and SINE settings select sine wave shapes with the Time Alpha parameter controlling the number of periods from 1 to 8.
FC: Amp Level Save now has an option for 0 dB to allow saving a preset via a footswitch.
Fixed signal level into power amp a bit too high in 6160 models.
Fixed Compressor block Auto-Gain not being updated when changing types.
Fixed wrong op-amp clip threshold for DS1 models in Drive block.
Various other fixes and improvements.
seriously impressive considering the amount of work that goes into these things and how much more difficult you mentioned it is to code for the Axe III processor! 
