Use .wav / .flac formats for sound files. During the build process, files are converted to best match the target platform. Use Armory Project - Flags - Sound Quality slider to tweak the quality.

When playing a sound, use the returned audio channel to query playback state.

var audioChannel: kha.audio1.AudioChannel =  iron.system.Audio.play(sound);
trace(audioChannel.position); // In seconds
trace(audioChannel.finished);