SD card in read only mode + volume control of Pi-DigiAMP+

Help and Support Raspberry Pi
1

Hello guys,

I’m currently planning to attach my raspberry (currently the rpi3, the goal is to get the rpi0 running once I get my hands on it) to a ceiling speaker in my kitchen.
IQAudio Pi-DigiAMP+ will be attached to rpi and from there straight to the speaker, no additional amp.
The rpi will be stored “invisible” over the ceiling. The whole set up will be powered with a switchabel socket.

  • I’m wonderig if the SD card will be in read only modus if I choose “install to NFS server” in OSMC-Installer. This is important to me since the switchable socket will cause unexpected shutdowns and I want to minimize the risk of sdcard corruption.
  • Secound question: During set-up the installer is insisting on wired connection if installationto NFS server is choosen. Will it work with wifi as well (at a later stage of isntallation, after everything is well configured)?
  • As describred above I use the Pi-DigiAMP+ to controll the volume of my speaker. Installation worked without issues, however the volume is reset to maximum after each reboot. Is this a bug or a feature (I can imagine that this is supposed to be a feature of only a DAC is used or if the pi is connected to an additional amp)? If its a feature, whould it be possibel to hack the volume at boot stage (lowering it to e.g. -40dB)? Please note: I’m not speaking of the ALSA master volume. I still want to be able to adjust the volume with the remote control. I just want to aviod having maximum volume from the beginning.

I hope someone can help me with my question.

Best regards
Ralle

2

No one?!
Come on… There must be a way.

3

No

This is a very poor idea. You would be wiser to simply break the speaker circuit and just allow the pi to idle. It literally costs less than $7/year to idle.

No. A limitation of NFSRoot…

Have you ever gracefully shut down the pi? Did this behavior still occur? Kodi writes some current settings at shut down. If you’ve never allowed graceful shutdown then these writes can never occur.

4

Hello ActionA und thank you for your answer.

Have you ever gracefully shut down the pi? Did this behavior still occur? Kodi writes some current settings at shut down. If you’ve never allowed graceful shutdown then these writes can never occur.

I did. Actual I never did a hard shutdown so far. As of today I’m testing the setup on my tv to allow easier configuration of settings. Would switch to VNC later to realize maintenance.

5

Try decreasing this.

~/.kodi/userdata/guisettings.xml

...
    <audio>
        <mute>false</mute>
        <fvolumelevel>1.000000</fvolumelevel>
    </audio>
...
6

it was set to:

    <audio>
        <mute>false</mute>
        <fvolumelevel>0.340000</fvolumelevel>
    </audio>

I had lowered the volume to ~1/4 of maximum before last reboot. But volume was at maximum.
I reduced to ~3/4 of max and rebooted. I see guisettings.xml is updated on my NSF before reboot with

    <audio>
        <mute>false</mute>
        <fvolumelevel>0.700000</fvolumelevel>
    </audio>

After reboot audio is at maximum untill I start to decrease it manually.

7

By the way, I updated /etc/rc.local to get the AMP out of mute state (see this link).

I also added dtparam=audio=off to config.txt (see here)

8

Ok, this is strange now. When I reset audio to HDMI I get the same behaviour.
Same for my rpi2 running latest OSMC (non NFS boot, no Pi-DigiAMP+ attached). I tested HDMI and Analogue. The fvolumelevel setting is written to guisettings.xml at shutdown but being ignored at boot (always at 1 until to start changing volume manually).
My rpi1 (connected to another TV, no HDMI, audio set do analogue) does not act like this…

What am I overlooking here?

9

Ok, got it. It’s the HDMI.
Booting headless, simply with unplugged HDMI solved my issue.
Seems to be a feature as plugged in HDMI usually means that you use your TV or AMP as audio-out as well. In this scenario you would control volume by controlling the AMP/TV output volume :wink:
However, I do see some potential update in here. Selection an audio source other than HDMI in hardware settings should disable this feature of ignoring the fvolumelevel setting.