Either track down the original remote for the model, or get a universal one, try and get the type that searches for the code automaticly otherwise you will be hunting around for the remote code that is correct for it.
That shows the unit is switching them off somewhere. Perhaps on different modes or surround settings.
If you have a DVD marked THX that will have testing settings for the system. Then you will be able to found out if a setting on the amp is responsible for the loss of channels.
Have you checked that both appliances are compatible with ARC HDMI? If they are then it is probably a setting problem. You should check that the socket is set up on both devices to act in the right way.
Look at the graphics equalizer settings to see if you have selected large hall, large room or any other setting that is available. Then turn that setting off.
If you are talking about the driver cones in each of the units, then it's odd that they should have gone, unless they have driven too hard or damaged (say by a child poking them). Double unit speakers have a crossover built into that separates the sound into treble and midrange or bass.
If the sound coming out is "treble" the high frequency that shows the bass units are not working.
Make certain all the wiring is good to the speakers and if you can see the bass speaker check it is not damaged.
If you need to, go inside the units and connect a 1.5 battery across each speaker terminal for a second. If it "pops" then it's working.
The vocals are directed to the centre channel. If this is not connected or the connection is poor then it will mute the sound of the vocals.
If you want you can select stereo mode when listening to just music. Not the surround modes. Or you can check the centre channel is working and not switched off. Some amps have the ability to switch speakers off in different modes or settings.
The volume buttons have 3 functions... down and up and straight down... that's mute. if that does not fix it go to menu.. the gear icon click on audio, likely we switch to an external sound device like DTS Amplifier...
Tony Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/tony_a41fa0b801734e2f
