add conditional logic so DefaultToSpeaker is only used on iOS
add conditional logic so DefaultToSpeaker is only used on iOS

adamnemecek/AudioKit,audiokit/AudioKit,audiokit/AudioKit,adamnemecek/AudioKit,eljeff/AudioKit,audiokit/AudioKit,eljeff/AudioKit,adamnemecek/AudioKit,eljeff/AudioKit,eljeff/AudioKit,adamnemecek/AudioKit,audiokit/AudioKit