Aukey EP-T25 User Manual page 9

I've connected the earbuds with my smartphone but can't hear any sound
Double-check the volume level on your smartphone and the earbuds.
Some smartphones require you to set up the earbuds as an audio output
device before the audio can be transmitted. If you're using a music player
or other device, please make sure it supports the A2DP profile.
The sound isn't very clear or the caller can't hear my voice clearly
Adjust the volume on your smartphone and the earbuds. Try moving closer
to your smartphone to rule out the possibility of interference or wireless
range-related issues.
What's the wireless range of the earbuds?
The maximum range is 10m (33ft). However, the actual range depends on
environmental factors. For optimal performance, keep your device
connected within a range of roughly 4m to 8m and make sure that there
are no major obstacles (like reinforced steel walls) between the earbuds
and your device.
The earbuds won't turn on
Try charging the earbuds for a while. If the earbuds still won't power on,
please contact our support team at the email address given in Warranty
& Customer Support.
I put the earbuds back in the charging case, but the earbuds are still
connected
The charging case is probably out of power. Try charging it.
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