Am I reading the information correctly that the sounds only come through the cell phone or do the units have there own installed speaker?
For the currently available Bachmann HO locomotives equipped with Bluetooth --
Quote from: Yardmaster on December 23, 2015, 08:57:43 PM
The sound comes directly from the app through your device's speaker. You can pair your device with a Bluetooth speaker which provides very dynamic sound when placed near your layout or use your ear buds plugged into your device for a more immersive experience.
Are there any plans for the sound to come from the locomotive on board such as other sound decoders?
Perhaps in the future.