HT41899 Overview - Buttons & Indicators

Audio input indicators: These indicate which input port you used to connect to your TV: AUX or OPT. USB indicates the USB power connection.

Codec indicators: These indicate which audio codec is active: SBC, FastStream (FS), aptX, or aptX Low Latency (LL). The codec will influence the audio quality and audio delay that you will experience.

Starting from Batch number T22H1 (How to find the batch no.), the buttons on the headphones look a little different. Please see the visual below (the transmitter remains unchanged).