My receiver will randomly lose audio output. If I
My receiver will randomly lose audio output. If I turn up the volume all the way, I can hear the audio at a very low level. The audio I hear is not distorted. It is almost like it goes into the mute mode by itself. When this happens I am unable to get it to recover. It may or may no work correctly the next time I power it up.
Audio Players & Recorders - Mitsubishi - M-VR700
Answers & Comments
Sounds like a loose connection. What audio source are you using? If you switch sources, does the other source have the same problem?
The volume control is ahead of all the inputs so the problem is before this and common to it. When the problem is there, try switching inputs to different sources, several times to see if the problem clears. If not, try a shock test....lift just the front of the receiver about a half inch and drop it. Does the sound level return?
I bought a Mitsubishi M-VR700 which produced no audio from the speakers, but with headphones, a tiny bit of audio was detectable with the volume on max.
the following solution was posted on FixYa by Mojorisin65 some time ago: "Facing the receiver directly behind the MITS logo & power button is a vertical board with a large IC on it, try flexing the board near the IC while turning the reciever on & off or changing input modes, there is a cold solder joint on this board which I haven't found yet. I understand this is a common problem with the MITS M-VR700-900, Onkyo TXDS-575, & Integra DTR5 or DTR5.1 ( all made by Onkyo)."
I gently flexed the board as described, and Boom, all audio was back as it should be. I suspect Mojorisin65 is correct about the cold solder joints, but with SMT components,it could be very difficult to find. It may very well be on one or more of the 48 pins on the large IC. This IC gets rather warm during operation, which may explain why some units work until it heats up. The chip gets warm and 'twists' enough to lift the bad pin(s). In an attempt to deal with this symptom, I superglued a TO-220 heat sink to the top of the IC (don't let it touch the case of C-716). The heat sink is dissipating a fair bit of heat,and so far, this 'fix' seems to be doing the trick. RJD 10.18.11