The red indicator flashing may be occurring because the battery life in the station is low and is not sufficient enough to connect with the phone. By plugging in the station or replacing the battery the red flashing should go away and images should be visible on the screen.

Make sure that you are plugging into the outlet completely, if it is only plugged part way it may not work. It is possible since you used multiple chargers that the outlet is not working properly. You should try another outlet and see if it charges.

I would start by making sure the device isn't on mute and turning the volume up some to try to hear. If that doesn't work you should go into the settings, then sound, and try to change it from there. If none of these answers helped it is possible that the speakers blew out and that you will need to replace them.