LG does not release frequent updates for the NB4540 (manufactured circa 2014–2016), but specific updates exist to fix Bluetooth pairing drops, volume control synchronization, and audio codec support. Here is the definitive method to check, download, and install an update.
For older models (pre-2024), LG recommends using the dedicated LG Soundbar App rather than the newer ThinQ app. lg soundbar nb4540 software update
You must know your existing software version to determine if an update is necessary. Follow these steps: LG does not release frequent updates for the