Letsfit U8i User manual

Bluetooth Headphones
User Manual
Thank you for purchasing our products, please read the
user manual carefully before use.
U8i

Package Contents................................................
At a Glance..........................................................
Wearing the headphones.....................................
Using the Headphones........................................
FAQs....................................................................
Specifications......................................................
SAFETY AND WARRANTY.................................
1
2
3
4
8
10
11
English Version

①Bluetooth headphones × 1
②Eartips × 4 pairs (L / M/ S/ XS; M-size
eartips pre-installed)
③Charging cable × 1
④Wire button (removable) × 1
⑤Carry bag × 1
⑥User manual × 1
Package Contents
-1-
XS
⑥
⑤④
③
②
①

-2-
At a Glance
②MFB button
(multi-function button)
③Volume +
④ Volume −
⑤LED indicator
⑥Charging port
② ⑥
③ ④
⑤
①Microphone
①

LED Indicator Guide
1) Identify the right and left earpieces.
2) Insert the earbuds into your ears.
3) Adjust the ear hooks until you feel
comfortable with it. To determine the best fit,
you may need to try all sizes of eartips.
Wearing the headphones
System State
Power on
Power off
Pairing
Connected
Charging
Fully charged
Low battery
Indicator Activity
The indicator stays blue for 1 second
The indicator stays red for 3 seconds
The indicator flashes red and blue
alternately
The indicator flashes blue once
every 10 seconds
The indicator stays red
The indicator stays blue
The indicator flashes red 3 times
every 5 minutes (with a voice prompt)
-3-

-4-
Using the Headphones
Charge the headphones
1) Open the hinged door on the bottom of the
right earphone.
2) Plug the small end of the charging cable into
the charging port of the headphones.
3) Plug the other end into a USB wall charger
or computer (DC 5V) that is powered on.

Power on / off
● Power on: Press and hold the MFB button for
1 second.
● Power off: Press and hold the MFB button for
3 seconds.
Pair
1) Turn on the Bluetooth of your Bluetooth devices.
2) Turn on the headphones and the headphones
enter pairing mode (indicator flashes red and
blue alternately).
3) In the list of found Bluetooth devices in your
Bluetooth device, choose "U8i" to pair.
-5-
Notes:
●Fully charge the headphones before using
them for the first time.
●The indicator is red during charge and turns
blue when the headphones are fully charged.
Settings Bluetooth
Bluetooth
U8i Connected 
MY DEVICES
OTHER DEVICES
100%9:41 AM
U8i
MY DEVICES

Function
Play / Pause
Volume up /
down
Previous / Next
track
What to do
Press the MFB button
Press the Volume + / Volume - button
Press and hold the Volume - / Volume +
button for 1 second
Notes:
●When the headphones are on but not paired
with your Bluetooth device, they will be
automatically off in about 5 minutes (to enter
pairing mode again, turn on the headphones).
●The headphones will directly enter pairing
mode the first time you turn them on, and
each time you turn on your headphones, they
will automatically connect to your last
successfully connected device if available
within the Bluetooth range.
●To have the headphones enter the pairing
mode when they had been paired with a
Bluetooth device, turn off the headphones and
press and hold the MFB button for 5 seconds
(indicator flashes red and blue alternately).
-6-
4) Enter "0000" or "1234" if your Bluetooth device
asks you to enter a code to pair.
Headphones functions

-7-
Function
Answer / end a call
Reject a call
Redial the last
number
Activate Siri or
other voice
assistant software
What to do
Press the MFB button
Press and hold the MFB button for
1 second
Press the MFB button twice
Press and hold the Volume + and
Volume - button simultaneously
for 1 second
Call functions
Reset the earbuds / clear all pairing
information on the earbuds
1) Connect the headphones to a power source
for charging.
2) Press and hold the MFB button for 5 seconds
until you hear a "Du" sound.

-8-
Q: I paired the headphones with my phone
before, but I failed to pair them with my
phone again.
A:1) Turn on the Bluetooth of your phone and
in "MY DEVICES", choose "U8i" and tap
" " → "Forget This Device".
2) Turn off the headphones.
3) Reset the headphones.
4) Fully charge the headphones.
5) Pair the headphones with your phone
again following the instructions in the
previous part "Pair".
Q: I paired the headphones with my phone,
but there is no sound from the
headphones.
A: Make sure the headphones / phone are / is
not muted. Some phones ask for the setup
of the wireless headphones as an audio
output device before a sound is transmitted.
Please refer to the instructions of your
phone for details. If you use a music player
or other devices, please make sure it
supports A2DP stereo music profile.
FAQs

-9-
Q: The connection between headphones
and phone is not stable.
A: Make sure your headphones stay close to
your phone (not away from your phone
more than 33 feet, no obstacles between,
and no radio or Wi-Fi interference nearby).
For Android phone users, if using aptX HD /
aptX and connection is unstable, please go
to the headphones setting of U8i in the
Bluetooth settings and disable the high
sound quality function.
Q: Can I use the headphones during
charging?
A: No, you can’t use the headphones during
charging.
Q: My headphones will not switch on.
A: Please recharge the headphones and make
sure they have enough battery power. If
they are fully charged and still nothing
happens or if you are not able to charge the
unit, please contact our customer support
for further information.

-10-
Specifications
Model
Bluetooth Version
Battery
Charging Time
Waterproof Rate
Input
Playtime
(varies by volume
level and content)
Bluetooth Range
Supporting Protocols
Supporting Audio Code
CVC Noise
Cancellation
Working Temperature
U8i
V5.0
100mAh / 3.7V
Approximately 2 hours
IPX7
5V / 1A
14 hours
10 m / 33 ft.
A2DP / HFP / HSP / AVRCP
SBC / aptX / aptX HD
CVC 8.0 noise cancellation
microphone
-10°C to 40°C

-11-
Important Safety Instructions
● Use of headphones will impair your ability to
hear other sounds. Use caution while using
your headphones when you are engaging in
any activity that requires your full attention.
● If you have a pacemaker or other electrical
medical devices, you should consult your
physician before using this product.
● This package contains small parts that may be
hazardous to children and should be kept out
of reach from children. This product is not a
toy – never allow children to play with this
product. Always store the product out of reach
from children. The bags themselves or the
many small parts they contain may cause
choking if ingested.
● Never try to dismantle the product yourself, or
push objects of any kind into the products, as
this may cause short circuits which could
result in a fire or electric shock.
● None of the components can be replaced or
repaired by users. Only authorized dealers or
service centers may open the product. If any
parts of your product require replacement for
any reason, including normal wear and tear or
SAFETY AND WARRANTY

-12-
breakage, please contact us.
● Avoid exposing your product to heat and
humidity to protect against damage to the
product or injury to you.
● Keep all products, cords, and cables away
from operating machinery.
● If the product overheats, if the product has
been dropped or damaged, if the product has
a damaged cord or plug, or if the product has
been dropped in a liquid, discontinue use and
contact us.
● Do NOT use in areas where there are
explosive hazards.
● Do NOT submerge the headphones in water.
Do NOT expose the headphones to moving
water (e.g., from a faucet, etc.).
● Do NOT wear the headphones while
showering or bathing, or when participating in
water sports, e.g., swimming, waterskiing,
surfing, etc.
● This product contains magnetic material.
Consult your physician on whether this might
affect your implantable medical device.
● Leaving the product in hot or cold places,
such as in a closed car in the summer and
winter conditions, will reduce the capacity and
lifetime of the headphones.

-13-
● Dispose of the product according to local
standards and regulations.
● Remember: Always drive safely, avoid
distractions and follow local laws!
Using the headphones while operating a
motor vehicle, motorcycle, watercraft or
bicycle may be dangerous, and is illegal in
some jurisdictions, just as use of the
headphones with both ears covered while
driving is not permitted in certain jurisdictions.
Check your local laws. Use caution while
using your headphones when you are
engaging in any activity that requires your full
attention. While engaging in any such activity,
removing the headphones from your ear or
turning off your headphones will keep you
from being distracted, so as to avoid accident
or injury. Do not take notes or read documents
while driving.
WARRANTY
We strive to build our products with the highest
attention to detail and craftsmanship. However,
sometimes there are occurrences of a defect, so
we are happy to offer a ONE-year hassle-free
warranty to all our devices as we continue to
make amazing products. Please contact us if
you have any questions about our devices.