receiver (headset), the silent or sound small

Examination and treatment:
(1) menu of the volume settings are correct?
(2) headsets have any questions? Normal headphones its DC resistance is about 30Ω, but also in the table with three measurements used to hear "giggle." Sound (in the mobile phone headsets generally use moving-coil, a small number of piezoelectric -style).
(3) headset contact between the reed and the PCB well? Treatment Ibid.
(4), headphone audio amplifier is not working or related to the existence of the circuit cold solder joint?
(5) The receiver holes are blocked?

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