Nad t751 extremely low output

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  • Jvoid22
    Learning Member
    • Mar 2025
    • 7
    • Ireland
    #1

    Nad t751 extremely low output

    I've been trying to trace an issue with my NAD t751.

    1. Extremely low volume output on both left and right channels

    2. No output when surround mode selected.

    3. Doesn't matter if headphones or speakers

    4. Doesn't matter which input.




    I've bought an oscilloscope and I THINK I've traced it to the multichannel board. Audio goes from inputs to this board, then sent to the amplifier boards.

    I get a signal from my freq generator to the input of the "m62447sp" IC.

    It seems that the output pins of this chip are dropping the signal. Is this how it's supposed to operate or should the volume be increased and maintain waveform?

    I'm not sure if I've just found the issue or if I'm misunderstanding this IC.

    See attached docs.
    Attached Files
    M62447SP Output M62447SP input
    2 Photos
    Tags: None
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