Allow input echo for an Aux Track to be locked as enabled

[Promidi]

Turning off all input echo via the mix Module also turns off the input echo for Aux Tracks - effectively silencing them. 

If one has a project with many Aux Tracks, turning them back on is quite a chore (unless you group all of the Aux Track’s input echoes).

It would be handy if you can either lock an Aux Track’s input echo to “enabled” on a track by track basis or set it to not be affected when you turn off all input echo via the mix Module.