Yup. That's quite an old issue I have b*tching about for a very long time. This is what I believe from my analysis it should happend:
First of all the Volume Bar is practically an Android app. As such it uses RAM. When changing volume the Volume Bar may have been previously closed by Android to free memory. So it needs to be loaded in RAM, there may not be enough free RAM and so the kernel Linux starts the kswapd0 process (I monitored this myself). Which can be quite CPU consuming and, since it works with RAM which is shared, it may block some other CPU operations/processes.
Add to this that the Volume Bar is bugged. It even crashes to be clear. I could identify in the logcat (Android's log) a failure point, where the Volume Bar crashed and then it had to restart (after a minute or two). In general it may take many seconds to change the volume of 30-40 positions over 100. In other words that app is probably the worst piece of junk in these televisions. The best solution is to have an AVR/Soundbar and change the volume with its remote control.
Oh, same identical things for the Settings. Like when you watch a video and press the Action Menu button. Crashes included. Although the crashes are quite less frequent (but the video stuttering may get even more painful).
