The player, the sound image of normal, just sounds small, that extracting main chip CL680 normal, servo normal. Failure analysis of D/A conversion in CL680 or analog audio signal processing circuit. Open the cover audio signal directly by the amplifier input plug is respectively connected with the JN03 plug 7, 9AUDIOR, AUDIOL decode board output connection, the sound, the fault section in the analog signal amplification. Remove the power board, first test simulation of audio amplifier, microphone amplifier integrated circuit NE5532, 4558 4, 8 leg voltage, found that the negative working voltage is 0V; measured + 14V, 14V voltage regulator tube QP31, QP32 input voltage is 0V, RP31, RP32 found along the lines of insurance resistor circuit, respectively for 10., 47 Ω 1/2W insurance resistor replacement troubleshootingTWJservice manual download site