Observe the machine boot touched stereo decoder box hot in a few minutes, the audio signal from IC801 {1} feet output, to stereo box {12}, {13} feet, again from stereo box 15} {, {16} feet, output to IC1301 {and}, {25} feet, AV switch IC IC1301 is controlled by the CPU. From IC801 {1} feet by 10 u F capacitance to stereo box 15} {, {16} feet, sound. Considering the stereo codec price, purchase and this feature is temporarily useless, so it will soon be removing the stereo box, the stereo box {12}, {13} feet received 15} {, {16} feet of commissioning, found that only need to wait about 15 seconds sound appear normal, and in this way, every time you change channels need to analyze the circuit. The stereo codec is controlled by I2C bus, according to the characteristics of I2C bus, at every boot, or conversion channel when the CPU will be repeated for detection of this IC, this makes the process of time increase greatly, so this phenomenon. A careful analysis of the stereo box circuit structure, found that the internal circuit of digital processing and analog signal processing part, part of the digital power supply for 5 v, the analog part of the power supply is 9 v, the analog signal processing part of power supply disconnect (disconnect stereo box} {11 feet, stop the analog circuit part of the work and part Numbers continue to work), mount stereo box of commissioning, everything is normal, stereo box is no longer hot, suggesting that this stereo box of analog signal processing circuit is damaged and the digital part is good, after such processing machine back to normal after use.M88service manual download site