The upgrading instructions are as follows:
1. Please find attached the upgrading software, download and copy it to the first category of your USB flash drive （please make sure the USB flash drive is in FAT32 format and not over 32GB； Don't put any files or songs on the disk, only this software.）
2. Turn on the soundbar and insert the USB stick into the USB port of the soundbar
3. After the machine displays "USB" for about 8 seconds, the machine emits two beeps and the display screen shows "--", indicating that the upgrade is complete.
4. Unplug the USB stick after the upgrade is complete and restart the soundbar