Hmm ... some questions and some thoughts ...
1. As far as I am informed, my FX8 presets will not work on your AX8 and vice versa. So any presets from me will likely not help you.
2. Everything you have done regarding the db-settings, the FX loop connectivity and the GateEXP settings on the AX8 to reduce the Hiss of the JVM410 pre amp section was necessary. As long as you use one of the OD1 / OD2 channels in orange/red mode, you need to setup a GateEXP block to reduce the hiss from your JVM pre amp section.
What you can do is to try different parameter settings for Treshold, etc. to reduce the lack of responsiveness of your guitar.
But be aware: using noise gates is always a trade-off between reducing unwanted noise and guitar responsiveness. You just can find an optimum for that.
3. You have to make sure that you can isolate the problem to a root cause: guitar pickups, cable, amp channel(s), AX8, wireless device, quality of the electricity, etc. So you should exchange all the hardware, step by step. Some of them, you have already done (e.g. testing without your AX8).
Try different cables (by leaving all the rest of the signal chain the same), try it without the wireless device (by leaving all the rest of the signal chain the same), use a different guitar (by leaving all the rest of the signal chain the same), etc.
4. IMO any other (different sounding) noise (other than the Hiss from the JVM pre amp section) can come from:
a.) either your pickups and the distance how you are standing to your amp and/or
b.) external devices/sources, e.g. bad electricity/grounding, bad cables, your wireless device, etc.
5. I personally suspect your pickups (4a.) causes the Hum problems at a certain volume level (not shown at home) together with your JVM410 amp channel selection at a certain volume level. And you probably may stand a bit to close to your amp.
(The number 7 + 8 of your post indicates that as well).
I would check that first:
a. Does Hum noise increases by turning the guitar pickups to your amp?
b. Is the Hum noise mainly on the OD1/OD2 (orange/red) modes and not on the clean (green) channel mode?
If 5a. and 5b. applies, I would say that this is a pretty normal tube amp/guitar pickups "problem".
This type of Hum (coming from the pickups and NOT from other potential sources like bad electricity, wireless device, etc.) I initially had in my rehearsal room as well.
I therefore use the preset Noise Gate of my FX8 (should be the same in the AX8). See my settings some posts above as a starting point.
The noise preset Gate Settings and the GateEXP block settings have reduced MY unwanted noise (hum/hiss) to a minimum, I can live with.
If you cannot eliminate your Hum noise problem with these two type of noise gate-settings (and by accepting a certain amount of minimal noise which is hearable when the band is not playing), then something else is the root cause of your Hum noise.
In that case, any help from distance is more speculation and therefore difficult.
Hope that helps. May be others have some additional thoughts for help as well.
wolbai