As the title suggest. Since you already have the option under settings how bout just put a checkbox one could check to save this setting so it does not have to be reset every time.
There are a number of scenarios I could go through to show why this is a good idea but I won't bore anyone with that. In short though some tv's with lots of post processing can slow down the video and if you got the audio going to a amp directly this might cause a delay of up to a frame. Granted its something only certain people would notice but it would be nice to have this be a setting that Splash can remember. Only other ways around this issue are to use a AV amp or turn off any post processing the screen is doing that might be slowing things down. We are talking about a 15-20ms which most wont notice but this option would make Splash Pro golden.
Please consider it and thanks for the great player that's always improving.