A:Answer I had this problem with mine. The Quick Start Guide provided in the box does not include the manual pairing instructions - you have to get the full user manual from the TCL website. Here are the instructions for manually pairing the Alto 6+ subwoofer:
1. Make sure the sound bar and wireless subwoofer are properly connected to the power supply. Turn on the sound bar.
2. Press and hold the Input Select button (the one with the square with the arrow going into it) on the sound bar main unit or the remote control, until the 4 LEDs on the front of the sound bar start flashing.
3. Press the Pair button on the back of the subwoofer until the amber light starts to flash quickly.
4. The amber light on the subwoofer should go solid after a few seconds and the four lights on the sound bar should stop flashing. Once this happens they will be properly paired.
5. If the amber light on the subwoofer doesn't go solid after two minutes, pairing has failed. Unplug both units for 3 minutes, plug them back in, and repeat the process.
5. Once pairing is successful, power cycle the sound bar a couple of times to make sure that the subwoofer stays paired to the main unit. The amber light on the back of the subwoofer should go from solid to slow blink when the sound bar powers off, and then from slow blink back to solid when the sound bar powers on.
