DISCOVER D312U User manual

Telephone Headset
D312U

User Manual
D312U is a lightweight telephone headset with retractable headband.
It’s compatible with all kinds of mobile devices and computers,
supports the functions of playing music and HD web phone calls.
1. Design

1) Retractable headband
2) Microphone
3) 3.5mm AUX Connector
4) USB Connector
5) Volume Control
6) Volume “+”
7) Volume “-”
8) Mute
9) Microphone Mute
2. Button Function
Note: The led indicator is red only when microphone is
mute. Under other status, the indicator is blue.

No NameIcon Function
While playing music, short press to
pause or continue to play.
Short press “+” to volume up; Long press
“+” to make it up to maximum volume.
Short press “-” to volume down; Long press
“-” to make it down to minimum volume.
While in a call, single press the button,
microphone is mute, and indicator is red;
Single press the button again to back to a
normal status, and the indicator is blue.
Mute
Volume “+”
Volume “-”
Microphone
Mute
1
2
3
4

3. Connection

4. Operation Instruction
1) For Windows Computer
Step 1: Click on “Start” at lower left corner, and then click “Settings”.

Step 2: Input “Audio” in “Windows Settings”, and then choose
“Manage audio devices”.

Step 3: In sound options, choose “D312U” in the list of “Playback”
and “Recording”.
D312U

2) For MAC or iOS Computer
Step 1: Click top left corner of your screen and select “System
Preferences”.

Step 2: Select “Sound” from the list.

Step 3: In sound options, choose “USB Audio Device” in the list of
output and input.

5. Specication
1) Nominal Impedance (AC): 32Ω±15%
2) Rated working power: 10mW
3) E󰀨ective frequency range: 20Hz-20KHz
4) Microphone sensitivity: -42±3dB
5) Headset sensitivity: 115±3dB
6) Sound distortion: ≤3%
6. Common Problems
Q1: No sound in headset.
Solution: Ensure the connection is correct; ensure USB port of your
computer is in good condition; ensure the 3.5mm audio connector

plugs into the jack perfectly; ensure the mute function is o󰀨.
Q2: A sharp voice in speaker or microphone.
Solution: The volume maybe too loud or the microphone is too close
to your mouth. Please adjust your speaker to a suitable volume and
the microphone in a proper distance.
Q3: Hear some buzz sound when in a call.
Solution: Try to use another USB port. The contact for USB port
might be poor.
7. Points for attention
1) Using non-original accessories may cause low performance, body

damage, short circuit and warranty failure.
2) Disassembling your earphone may damage the earphone and
would be beyond our service warranty.
3) Do not use your earphone in a dusty environment.
4) Please use a clean, soft and dry cloth to clean your earphone.
5) Keep placing the earphone in its original package when not using
it.
6) Do not let your children play with the earphone. They may hurt
themselves or damage the earphone.
7) Do not place the earphone in hot or cold environment, otherwise
it may be temporarily unusable.