Diagnosis
Signal interference or a weak Bluetooth connection. The human body, especially near the hip, can block the 2.4 GHz signal. Other Wi-Fi or Bluetooth devices cause congestion.
How to Fix It
Reposition the speaker. Keep it at least 3 feet away from routers, microwaves, or other speakers. Ensure there is a clear line of sight between the speaker and your phone. Move your phone to a different pocket or hand. Power cycle both the speaker and your phone's Bluetooth.
If That Didn't Work
The issue may be with your phone's Bluetooth antenna, not the speaker. Test the Flex with a different audio source, like a tablet or laptop, from the same distance. If the problem persists, reset the speaker by holding the Bluetooth and Volume Down buttons for 10 seconds.
Heads Up
The silicone strap is not an antenna. Do not cover the speaker grille or the back panel with your hand, as this can also muffle the microphone used for voice prompts and calls.