Folks, may I please get some help with some various tests?
Test #1 with AMP15
With the AMP15, could some please see if you could toggle between PO and LO seamlessly both in Android mode and Mango OS mode with firmware 1.03.408? Once you've toggled to LO, then toggle it back to PO, do you get sound on both channels, or only 1 channel?
My results: I get sound only coming from 1 channel when switching back to PO. At the moment, the only way for me to restore proper behaviour is to Factory Reset, but I'll continue to find ways to try to restore normal PO later.
What are your results?
Test #2 (2 parts) AMP16
a) Very first time use of the AMP16 use (before switching any modes) - this one is a little bit more finicky as it requires a factory reset in the test
i) Factory reset the DX340 and you have your AMP16 plugged in
ii) I gather you should be in Output AB mode by default
iii) Do you get any sound?
My results: I don't get any sound (and at first I thought it was something wrong with my 1st AMP16 and Paul sent me another, and the 2nd was also the same.
My workaround/fix:
I have to switch Output Gain from AB mode to Tube then I get sound coming out of the AMP16. It's almost like an initialisation. And thereafter I can toggle back 'n forth between AB Mode and Tube mode. But if I factory reset, I'll end up back with (2a again).
If you're prepared to try a factory reset, what are your results?
Observations after I do get sound out of the AMP16: I noticed AB mode is a lot softer in volume than Tube mode. And this leads to part b of Test #2 below.
b) AMP16 Amp Gain settings without SuperGain (i.e. without 12VDC-In)
i) can you try switching between the AMP Gain modes L->M->H
ii) do you get the gain increasing in order as expected? i.e. lower volume, medium volume higher volume with L/M/H gains?
My results: I find my volumes from the AMP Gain L/M/H result more like L/H/M instead - i.e. Low Gain -> low volume (OK), Medium Gain -> high volume (not OK), High Gain -> medium volume (not OK). This is irrespective of AB or Tube mode (just that AB is a softer range than Tube range), and it doesn't matter if it's MangoOS or Android.
If SuperGain is enabled (whilst 12VDCIn plugged in, then unplugged), the AMP Gain L/M/H behaves as expected in increasing Gain. But disabling SuperGain (whilst 12VDCIn plugged in, then unplugged), then the AMP Gain L/M/H again misbehaves with as L/H/M.
What are your results?
P.S. I'm trying to differentiate between user error (i.e. my stupidity) vs bug in firmware (i.e. others can replicate) vs my specific DX340 or AMP unit issue