User's Guide

Sound Prompt
Warranty Description
Product Parameters
Hearing Protection
Safety Precautions
Common Problem
Contact Us
① Do not use it too long under high volume as it may damage your hearing
② Do not use too high volume in case surrounding sound cannot be heard
① Please avoid heavy drop or bump
② Please use original or qualified charging cable.
③ Do not disassemble or modify the earbuds yourself to prevent damage or
danger.
④ Please avoid the earbuds from water contact and keep it dry
⑤ Please keep the earbuds away from children as it may damage their hearing
⑥ Do not use earbuds in lightning weather to prevent accidents
⑦ Wipe with a soft, dry cloth to avoid irritating chemicals or strong detergents.
⑧ Do not use this product in severely hot / wet / corrosive environments.
① Contact number: 4006131096.
② Official website: www.jiayz.com.
③ Address: Building A16, Silicon Valley Power Intelligent Terminal Industrial
Park, Guanlan Dafu Industrial District, Shenzhen
Q: The earbuds cannot turn on automatically?
A: ① Check if the charging case has power.
② Check if the earbuds are low powered
③ Check if the earbuds can be turned on manually
Q: Bluetooth signal is not stable?
A: ① Check if there's electromagnetic interference surrounded
② Check if the earbuds are too far from device
③ Restart the phone, to prevent the problem of mobile phone signal
instability.
④ Turn off the wifi and try again
Q: How to tell if the earbuds are fully charged?
A: ① The earbuds charging time is about 1.5 hour.
② When fully charged, the earbuds blue light will steady for 7s and then
turn off
Q: The earbuds cannot be charged?
A: ① Make sure the earbuds charging contacts are clean
② Whether the earbuds are placed in the charging case.
③ Whether the charging case has sufficient power.
Q: How to adjust the earbuds volume?
A: ① Long press the left earbud for 1.5s to decrease volume, long press right
earbud for 1.5s to increase volume.
② When you adjust the volume, most Android phone won’t display the
change, you need to feel the volume change yourself(There's 15 grades
volume in total)
Q: How to connect earbuds with device?
A: ① Turn on the earbuds and wait until blue indicator lights flash every 0.5s,
which means earbuds is pending for connection
② Turn on bluetooth function from your device and connect bluetooth
named “BY-AP1”
Q: No sound from the earbuds?
A: ① Check if the earbuds are connected to the mobile phone, and whether
the media audio is selected.
② Check if the earbuds volume is adjusted to the mute state.
③ Check if there's electromagnetic interference surrounded or if the
earbuds are too far from device.
NOTE: This equipment has been tested and found to comply with the limits
for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits
are designed to provide reasonable protection against harmful interference
in a residential installation. This equipment generates uses and can radiate
radio frequency energy and, if not installed and used in accordance with the
instructions, may cause harmful interference to radio communications.
However, there is no guarantee that interference will not occur in a particular
installation. If this equipment does cause harmful interference to radio or
television reception, which can be determined by turning the equipment off
and on, the user is encouraged to try to correct the interference by one or
more of the following measures:
- Reorient or relocate the receiving antenna.
- Increase the separation between the equipment and receiver.
-Connect the equipment into an outlet on a circuit different from that to which
the receiver is connected.
-Consult the dealer or an experienced radio/TV technician for help
Changes or modifications not expressly approved by the party responsible for
compliance could void the user's authority to operate the equipment.
This device complies with Part 15 of the FCC Rules. Operation is subject to the
following two conditions:
(1) this device may not cause harmful interference, and (2) this device must
accept any interference received, including interference that may cause
undesired operation.
Warranty Service
12-Month Quality Warranty Lifetime Technical Service Support
① Within 1 year since the customer purchase this product, we will provide
free warranty service in case the damage is caused during normal use.
② Under the following circumstances, the free warranty will be refused. We
will however provide free repair service but charging fees for parts.
A. The product has been mishandled, inadvertently used, or damaged
due to irresistible movement.
B. The product is disassembled and repaired privately without the
company's permission.
C. The head unit is in the form of debris or impact, which causes the
diaphragm to deform, crush, and soak for a long time. Damage to the
casing, deformation, etc.
D. The using time exceed 1 year.
③ The free service provided by this warranty does not include product
accessories and other packaging, gifts products and so on.
R
BY-AP4
Package Content Product Structure Earplugs Wearing Power ON / OFF
Bluetooth Pairing
Earbud x 2 Charging Case x 1
Earplugs ( Pairs ) x 3 Type-C Charging Cable x 1
Warranty Card x 1
Instruction Manual x 1 User Guide x 1
Carrying Bag x 1
R
S
M
L
Instruction
Manual
Warranty Card
User Guide
Wireless Charger
True Wireless Stereo Earbuds
Earbuds Indicator
Microphone
Charging Pins
Power Indicators
(Charging case)
USB Type-C
Charging Port
Built-in Wireless
Charging InductionCoil
Left Ear
Please choose the pair of earplug with most appropriate size. Insert
the earbuds into ear canals as shown above, rotate it to your most
suitable, comfortable position.
Right Ear
Power ON / OFF Manually：
Auto Power ON:
Open the case, and the earbuds turn
on automatically
Auto Power OFF:
① Put the earbuds back to the case and close the cover.
② Haven’t operate or connect the earbuds beyond 5 minutes.
③ Being in ultra-low battery status.
① Turn ON: long press left / right earbud for 2.5 seconds，
left / right earbud will turn on.
② Turn OFF: long press left / right earbud for 8 seconds，
left / right earbud will turn off.
Reconnect the device：
The earbuds will automatically reconnect to recent connected
device, after turn back on.
NOTE：for single-ear mode, take either left / right earbud out
from charging case until blue light flash per 0.5s, then
search "BY-AP4" for connection.
① Open the case, the earbuds turn on and automatically
pair with each other. After paired successfully, the main
earbud prompts “Du”, the auxiliary earbud prompts “DuDu”.
(main / aixliary earbud switch automatically) Blue lights on
left / right earbuds flash per 0.5s indicates pairing pending.
② Open the Bluetooth on your device, searching for the Bluetooth
named “BY-AP4” and select it to enter the paring mode.
AUTO ON/Bluetooth Pairing：
BY-AP4
① Long press left/right earbuds for 12s under off state, the earbuds
prompt “Power On”, “Pairing”, “DuDuDuDu” in turn, the red light of
earbuds steady 2.5s and then turn off, indicates the earbuds
successfully restored to factory setting.
② Place both earbuds back to the charging case, close the cover and
take them out after a short period, the earbuds will turn on,
automatically pair into binaural mode and re-search for pairing.
(earnids red/blue light steady 2.5s, then blue light flash every 0.5s)
This mode is for the pairing failed condition of earbuds only.
Earbuds Resetting / Restore Factory Setting Charging Guidance
Use the USB Type-C charging cable to
charge the case:
The indicators on the charging case flash
white in sequence. When fully charged,
the indicators glow solid white.
Use wireless charger to charge the case:
the indicators on the charging case flash
white in sequence. When fully charged,
the indicators glow solid white.
Use the charging case for charging:
Place earbuds back into charging case,
close cover, the left end / right end
indicators flash 5s and then turn off,
respectively indicates the left / right
earbuds is charging.
① Play / Pause：
Double tap left/right earbud
② Volume + / Volume -
Volume - : Long press left earbud for 1.5s
Volume + : Long press right earbud for 1.5s
③ Previous Track / Next Track
Previous Track：Triple tap left earbud
Next Track：Triple tap right earbud
④ Wake Up Voice Assistant
Tap left / right earbud 4 times
⑤ Calling Operation
Answer / Hang Up：Tap left / right earbud
Reject：Long press left / right earbud for 1.5s
Basic Operation
Indicator Light
Power On
Power Off
Bluetooth Connecting
Bluetooth Connected
Bluetooth Disconnected
Low Battery
Incoming Calling
Reject a Call
Over Distance
Restore Factory Setting
Maximum Volume
Minimum Volume
“ Power on ”
“ Power off ”
“ Pairing ”
“ Your headset is connected ”
“ Disconnected ”
“ Battery low ”
“ Mobile phone with ringtones ”
“ Call reject ”
“ Link lost ”
“ DuDuDuDu ”
“ DuDu”
“ DuDu ”
The above specification is sourced from the BOYA laboratory, and the
actual specification depends on the product or other factors. If you
have any doubt, please contact our support team
Bluetooth Name:
Bluetooth Version:
Frequency Response:
Transmission Range:
Earbud Battery Capacity:
Charging Case Battery Capacity:
Power Supply:
Music Play time:
Charging Time:
Bluetooth Profile:
Weight：
BY-AP4
V5.0
20Hz-20kHz
≥10m
50mAh*2
450mAh
5V / 500mA
Earbuds: Approx 6 hrs
(50%volume)
Charging case: Approx 16 hrs
Earbuds: Approx 1.5 hrs
Charging case: Approx 2 hrs
HSP / HFP / A2DP / AVRCP
Earbuds: 4.7g (0.2 oz)
Charging case: 40g (1.1oz)
Power On:
Power Off:
Connection Pending:
Connected:
Reconnection Pending:
Successful Connected:
Incoming Call:
Earbuds Charging:
Earbuds Low Power:
Charging Case Charging:
Charging Case Fully Charged:
Earbuds blue light steady for 2.5s
Earbuds red light steady for 2.5s
Earbuds blue light flashes every 0.5s
Earbuds blue light flashes every 14s
Earbuds blue light flashes twice every 4s
Earbuds red/blue light steady for 1.5s
Earbuds blue light flashes twice every 4s
Earbuds red light steady
Earbuds red light flashes every 14s
Charging case white light flashes
Charging case white light steady
Earbuds blue light steady for 7s and
then turn off
Earbuds Fully Charged:
FCC ID: 2ARN3BY-AP4