Input Pream gain (PGA Gain)

Hi there,

I’m trying to set the PGA gain (the input preamp gain I assume) to any other value than +21dB.

On the V5 itself I went into :

Mix -> Level -> Ctrls#2
Level is currently at +21.0dB
Change value to 0.0dB
Nothing changes in the sound.
Get out and return in this same menu and the value is back to +21dB.
Tried many permutation of this maneuver to no avail.

On the webconf I went in
Hardware -> Audio -> [...] button
Then checking both PGA Gain Left and Right to 0.0dB
Pressed"ok then save
To which after a while returned :
Zynthian needs to reboot to apply your changes!
and promptly clicked the nuclear nuke inspired REBOOT NOW! button.

After reboot. No change whatsoever.

Redid the very same webconf adjustment (twice now) and after booting the input gain was finally audibly 20ish dB lower in volume.

But then I went in the level menu again of the V5 itself and just looking at the menu made it jump to PGA +21.0dB and bam, the volume changed back to an audible 20dB higher.

I search for this issue but neither the wiki nor the discord search engine turned fruitful.

Any hints ?

Are you using latest stable image?
There are some fixes to the audio levels screen in the testing branch.
Perhaps you could try with the testing SD- image.


Loaded image 2311 and yes, Input gain is working as expected directly on the V5.

I is a now a very happy person.

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The latency in definitively lower or am-I hallucinating ?

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humm, the gain still changes (audibly and in the UI) for no apparent reason. I have not yet figured how to reproduce reliably… Can we lock the gain and level ?.

Transcript :
So, I’m in the audio level [menu]. And if I [just] touch the level of the input, it “jumps” to a high level [even if] the gain is still at zero [in the interface]. And if I touch it [the gain], I goes really to 0.0dB and If I go back and just touch the volume, it jumps right up.

I’m speaking in an SM58 the whole time.