I have just purchased from Amazon . ( sound core boost)
When I got it , easy to pair via bluetooth with iphone.
It worked fine .
After 3 weeks , NO sound is coming.
I try to re-pair with my phone , It 's successful pair but still NO sound.
I try to use my android phone and others device to pair with my sound core boost.
All of my devices can successful pair. but NO sound.
Please help.
Thanks
Note
Hello @ranjithet,
sorry to hear, that you have a problem with the device. Can you please try to use the speaker via the audiojack. What happens if you set the speaker to maximum volume, then comes a tone that makes this recognizable?
If you still have a problem with the speaker, contact the Anker support via: support@anker.com and call them the problem, the serial number of the device and the Amazon order number. 
Make sure in settings, you have audio set to play through the BT device.
Also check if using true audio, where your phone controls the audio volume. (Not sure if the proper name, but it’s in BT settings also).
You should try a hard reset of the speaker. I’m not sure how to do a hard reset of this particular model.
@ndalby May know how…
Is it not BT 5? May r it’s older Bluetooth?