If you start artsd from the KDE control panel, the default is to suspend after 60 seconds. If you start artsd from the command line you need to use the -s option to specify the autosuspend time, otherwise it will default to disabling the autosuspend feature.
Currently it doesn't suspend when using full duplex. Turn full duplex off from the KControl and it will suspend. Disabling full duplex is generally a good idea anyway if you only use aRts for playing audio and not recording.
Run them using the artsdsp. For instance, if you normally would run:
% mpg123 foo.mp3
instead use:
% artsdsp mpg123 foo.mp3
This will redirect the sound output to aRts. This method doesn't require changes to the applications. It is something of an ugly hack however, and does not yet fully support all features of the sound card device, so some applications may not work.
5 Are there theoretical limitations with some applications that will prevent them from ever working with artsdsp?
No. Using artsdsp can result in slightly more latency and CPU usage that using the aRts APIs directly. Other than that, any application that doesn't work should be considered a bug in artsdsp. The technique used by artsdsp should, if implemented properly, allow every application to work with it (including large applications like Quake 3).
You can wait for artsd to suspend or use the command artsshell suspend to ask the server to suspend itself. You will only be able to suspend the server if no aRts applications are currently using it, and no aRts applications will be able to run when the server is suspended.
If the server is busy, a crude but effective way to get rid of it is:
% killall artsd ; killall artswrapper Now start your own application. % kcminit arts
Any currently running aRts applications may crash, however, once you kill the server.
If you are running KDE 1.x applications, which output sound via the KDE 1 audio server, you will need to run kaudioserver to make it work. You can start kaudioserver in the same way than other non-aRts-applications:
% artsdsp kaudioserver
You will need to have installed kaudioserver (from the same source where you got your KDE 1.x applications from) - it belongs to KDE 1.x, not KDE 2.