If TuneBrowser disabled volume control, there are almost two reasons:
- Doing DSD native playback.
- Bit Perfect enabled (BP1/BP2).
It seems that you are playing DSD data. Usually, if the device supports DSD native playback, player software cannot control volume. This is due to the DSD characteristics.
You are using Conexant SmartAudio HD. I don’t know whether it is supporting DSD native playback.
If you cannot determine a reason, please upload screenshot of right-down corner (indicators area) of Player View.