I will assume you are using the Fire TV Stick 4K (the newest model.) This will work with all TVs which support HDCP 2.2 through HDMI. Previous versions of the Fire TV Stick don't have this requirement. Since it appears you are getting video and not audio, this isn't likely the problem, but I would recommend checking your available HDMI ports on your TV to see if any are labeled ARC or eARC and change to that port if it isn't already plugged in there, just in case.
Also, if you are using a surround sound system connected to an A/V receiver, the Fire TV Stick will not work with surround sound unless it is plugged into an HDCP 2.2 port on the A/V receiver itself (if plugged directly into an HDMI port on the TV, it will only play through TV speakers.) A/V receivers don't usually mark their ports as ARC or eARC so you'll want to look for one that says "BD" or "BluRay" as those are 4K ports and will be compliant.
If you are connecting through the A/V receiver, make sure that your TV 's input is set to the HMDI the receiver is connected to, and the input for the A/V receiver is set to the port the Fire TV Stick is plugged into.