So what you're saying that if you currently have adjusted alsamixer so that you have sound coming out of your headphones:
* if the "Speaker" volume is turned all the way down to -48 dB (without muting it, just turning the volume all the way down), suddenly your headphones mute.
* if the "Speaker" is -47 dB your headphones are unmuted
* if the "Speaker" is 0 dB your headphones are unmuted
* regardless of "Speaker" is -47 dB or 0 dB, headphones have the same volume.
So what you're saying that if you currently have adjusted alsamixer so that you have sound coming out of your headphones:
* if the "Speaker" volume is turned all the way down to -48 dB (without muting it, just turning the volume all the way down), suddenly your headphones mute.
* if the "Speaker" is -47 dB your headphones are unmuted
* if the "Speaker" is 0 dB your headphones are unmuted
* regardless of "Speaker" is -47 dB or 0 dB, headphones have the same volume.
Is this correct?