No speaker sound with hk 3480.

You need to set the device on the aux mode. Connect the cable at aux. Sign at the back of the device

good luck

prob with the audio amph on the motherboard

Is this a new installation or did this problem just appear spontaneously?

Perhaps MUTE is on. Don't troubleshoot this with the power turned up because you may suddenly find a wrong settign and blow up you speakers.

These means that the output stage is already blown out (maybe from pre-used short circuit speakers' cables). I suggest you to get it at a technician in order to locate and replace the blown parts.

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Stelios
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Remove speaker wires and try again. If it still goes into protect mode, the problem is internal...shorted power transistors or some other fault. Check fuses also.

Check the speaker wires.
Make sure your ohm loads are stable especially if you are using more than one pair of speakers to any output.
Check the starting volume.

your fuses are blown by possible crossing speaker wire - and + together. I did this and kept turning it on but I ended up frying the unit. Check your wires and make sure that they are seperated properly. If problem continues then unscrew the shell and replace 1 or all 3 fuses (depending on what was blown) with GMA 8 amp fuses. good luck.

Is the buzzing coming over the speakers or just from the receiver itself?
If over the speakers:
Try swapping ports on the receiver from the DVD. Go from DVD into an auxiliary video or VCR 2 if available.
Try swapping out the cables with known good ones.
But do this in steps to be able to nail down the problem and not just leave a mystery.
If the sound is solely coming from the receiver it could be a dusty fan. Blow it out with compressed air ,With the Power Off.
Or, my favorite, might just have to crank it up so you can't hear the buzzing.
good luck
COEch

have you ever been able to hear anything from this unit?

Sounds like a bad output channel is causing it to go into protect mode. Time to see a repair tech.