05TV242
KDE-P42XS1, KE-P42XS1 BC
Subject IRIS
Buzz Noise from Speaker at Minimum Volume 1545
SYMPTOM
Depending on the contents of the picture, a buzz noise composed of several low-frequency components and their
harmonics may be audible from the speaker (not the tweeter), even at minimum volume. In a completely silent
room (21 dB SPL) and with the set at maximum power supply load (white picture), the noise could be heard from a
1.5~2 m distance.
CAUSE
The signal ground is insufficiently isolated from the power supply ground of the panel driver.
SOLUTION
• On the G Board, make a wide and clean cut across the ground pattern as indicated below, avoiding to cut the
thin pattern in the vicinity.
