Thank you very much for purchasing the B2 Wireless Speaker! Please read the user manual carefully before using this device. If you have any problems or suggestions for this device, please feel free to contact us.

Product Specification
Package Contents
Warranty Information
About Fosi Audio

Product Specifications

Thank you very much for purchasing the B2 Wireless Speaker! Please read the user manual carefully before using this device. If you have any problems or suggestions for this device, please feel free to contact us.

Our email address is: support@fosiaudio.com


  1. It is normal for the product to slightly heat up during charging, please don’t worry.
  2. Please cut off the power of the speaker while cleaning.
  3. Please do not use alcohol, benzene and other chemicals to clean the cabinet.
  4. Please keep this product away from objects that are too cold or too hot.
  5. Please use the accessories provided by our company. 
  6. Do not disassemble the speaker by yourself.

Product Specification

Bluetooth Version

JL 5.0


Voltage Input

DC 5V/2A


Output Power






Product Dimensions



Product Weight



Operating Environmental Temperature


Package Contents

B2 Wireless speaker * 1

Type C charging cable * 1

Product manual * 1

Hook * 1



  1. The speaker is on, searching available device “Fosi Audio B2” to pair. The indicator is on when the speaker is paired successfully. The indicator is flashing while music is playing. The speaker will automatically connect back to the device within 30 seconds of turing it on again if the speaker was paired. 
  2. Long press the “▷” button for 2 seconds to disconnect the Bluetooth device. The speaker will power off after 10 minutes automatically without Bluetooth connection. 
  3. Long press the “⟁” button for 5 seconds to clean the Bluetooth paired devices list of speakers. 

    For IOS system, you can synchronize the volume up or down on the mobile phone.   

      – Volume down/ Previous song 

      + Volume up/ Next song

      ▷ Play/ Stop

 Under True wireless stereo pairing mode, the main speaker will answer the incoming call. 

True wireless stereo mode

  1. Turn on two B2 speakers, don’t connect them with your phone first. Long press the “⟁” button of either speaker for 2 seconds, the prompt tone sounds, both speakers will be connected together automatically. Then turn on the Bluetooth of your phone to search available device B2 to pair. Once successfully, the blue indication keeps flashing which is main speaker. The blue indicator keep on which is hub speaker. 
  2. Under stereo pairing mode, the indicators of both speakers keep on. Then, the indicators turn into flashing while playing music. 
  3. Long-press “⟁” button of either speaker for 2 seconds to end the stereo pairing mode. But the Bluetooth connection won’t be disconnected with the main speaker. 

Please fully charge the speaker for the first time uses, the full charging time is about 3-3.5 hours. When charging, the indicator is keeping red, the red light goes out after charging finished. (Note: If the product is not used for a long time, please fully charge the product at least once a month to avoid excessive discharge, which will affect the service life of the battery). 

Low power warning

When the power of the speaker is lower than 20%, you will hear the prompt sound of low power. Please charge the speaker with the included type c charging cable DC5V/2A in time. When the power of the speaker is lower than 5%, the speaker will be shut down automatically. 


Q1: The speaker cannot be reconnected to the phone automatically when it is turned on.

  • Please delete the paired connection record B2 on your device, then search the B2 to connect again.

Q2: The phone cannot search out the Bluetooth B2.

  • Please keep the phone and speaker in the Bluetooth rang of 10 meters. The search distance varies depending on the connected device. 

Q3: The speaker cannot make voice calls.

  • Please select speaker as sound output way on the call interface.

Q4: The true wileless stereo cannot be connected.

  • The effective range of True wireless steoreo interconnection is about 5-8 meters. Keep the device within the range and try again. (Please follow the true wireless stereo pairing instruction).

Q5: The speaker cannot be turned on.

  • If the speaker is not used for a long time, the battery will be consumed naturally. Please give it a charge. 

Warranty and Maintenance

All Fosi Audio products have an 24-month limited warranty on parts and labor from the date of purchase. Please contact us if you have any problems.

About Fosi Audio​

• Fosi Audio designs and builds innovative audio products with all your music in mind. Great sound, simple but elegant designs, high-quality materials, and truly useful features are what Fosi Audio is about. We sincerely hope you get as much enjoyment from our products as we’ve had to create them!

Our website: www.fosiaudio.com

Amazon store: www.amazon.com/fosiaudio 

Our Youtube channel: Fosi Audio

Our Facebook page: Fosi Audio

WhatsApp: +8613716612254

Call us: +49 33389171782

After-sale Service and Technical Support Email:  support@fosiaudio.com