Vista M22: How to Replace the Batteries
The M12 amplifier can use either 2 "AA" batteries or an AC power supply (sold separately):
The battery compartment of the amplifier is located on the left side of the unit.
To replace the batteries:
- Remove the battery cover by pushing it down towards the bottom of the amplifier.
- Insert the two AA batteries into the amplifier. Be sure to match the + and - symbols inside the compartment.
- Replace the battery cover by sliding it up into place.
- When the batteries are low, you will hear three beeps through the headset.
- You also have the option of powering your amplifier using an AC power supply, which is sold separately