ID 480729 - Knobs are not updated when using knobDefaults() for ari/r3d file types

Problem summary
The Python function for knobDefault() does not change values when setting specific knobs for ari/r3d file types.

Customer reported version
nuke.12.2v7

Customer reported platform

Steps to reproduce
1) Add the following snippet to the init.py file in the .nuke directory: 

2) Launch Nuke, then Read in an .ari or .r3d file.
3) View the Properties for the specific colorspace.

Expected behavior
The knobs should be adjusted for the knobDefault() values.

Actual behavior
The knobDefault() function does not affect the ARI/R3D knobs.

Workaround
There are no available workarounds at this time.

Reproduced by Support in:
Nuke 13.0v2 - Windows 10, macOS 10.14
Nuke 13.0v1 - Windows 10
Nuke 12.0v1 - Windows 10
Nuke 11.0v1 - Windows 10
Nuke 10.0v1 - Windows 10
Nuke 9.0v1 - Windows 10
Nuke 8.0v1 - Windows 10, macOS 10.14

Earliest version tested
Nuke 8.0v1- This issue appears to be in all versions of the product