Hisense LCD TV LED42K310X3D no sound troubleshooting - Home Appliances

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The Hisense LCD TV model LED42K310X3D has no sound, but the image is normal and there's no boot sound. I first tried restoring factory settings, but the issue remained. After disassembling and checking, I found that the audio chip used is the TAS5707, a digital chip. I measured the power supply voltages: 16V and 3.3V were both normal. The bus lines at pins 23 and 24 also showed 3.3V, which was fine. The mute pin (pin 19) had 2.9V, which was also within range. I decided to replace the chip, but the problem still persisted. Upon further inspection, I noticed that the voltage at four key pins—AOMCLK (pin 15), AOLRCLK (pin 20), AOBCLK (pin 21), and OSDATA0 (pin 22)—was only 0.2V. That was unusual. I then disconnected the power and checked for short circuits, but everything looked good. By tracing the circuit, I found that these signals were connected to pin 95 of the main control chip MT5501. There was a resistor in the middle of the connection, and when I tested it, it wasn't showing continuity. It seemed like the resistor was open. I bypassed it by directly connecting the line, and after testing, the TV worked perfectly. This suggests that the original resistor might have been damaged or failed over time.