How to adjust speaker balance/ volume using ALSA APIs
I am new to ALSA and have started with configuring the ALSA config file .asoundrc . I am able to control percentage amount of output to different channels, be it 2 or 4. Let me explain how I do it : I create the configuration nodes in the .asoundrc . Then in the ttable I specify the %age amount for each channel. This way my different applications can use different nodes(currently am using mplayer) and accordingly control the %age amount of output to different channels. The problem I am facing is to have this configured on the fly i.e. during playback I actually want to vary the sound output, like we have in most of the players. Something like the Volume Balancer. How can this be done. Should we write into the .asoundrc and then restart the player or should one make use of the ALSA APIs to re-configure it. Please advise as I couldnt really find any API which could perform the same task on the run.
Thanks in Advance