My new found M9990 is barely audible even with the volume at maximum. The speakers are fine as I found out when I first switched it on and heard a full-on blast of static when I touched the volume knob!

It's the same on both tape and radio, wiggling the other switches and record button has no effect but I'll open it up shortly and clean the switches before doing anything else.
I was wondering why the volume knob was turned all the way up when I got it.

check the headphone jack and external speaker jacks if it has them to see if the sound is any louder ,

Thanks JVC floyd,
Just tried both of those and it's still the same.

does the radio tune in stations even at low volume ?it might be a bad function selector switch if not ,who knows i guess you will know more after you lube the knobs and switches plus check the voltage selector boxes do wierd things when the voltage selector is on the wrong voltage.

All radio bands work fine and tune in, there's no voltage selector on this one.

Since he touched the volume knob and heard full volume wouldn't that be a dead givaway to a VERY dirty volume pot or a bad solder connection at the volume pot? Fuzzyduck if you are going to spray the pot use Caig MCL. Be very careful of other concoctions since some use aggresive solvents. A little goes a long way, even with Caig MCL. Use just enough to correct the problem and watch for dripping and overspray onto other parts of the M9990 (especially painted areas).

Both Sanyo M9935K boxes I've owned had problems with the volume knob. If you get it fixed, please let us know. Maybe I can fix my Sanyo.

Thanks Analogboi,
I use Servisol Super 10 switch cleaner here in the UK, not heard of the one you mentioned.

I gave all switches and pots (including the record awitch) a good cleaning today but there's no change but the horrible static has now gone fron the volume control thank goodness.
I will have a look at that double volume pot tomorrow and see if there's anything amiss.

I forgot to mention that the VUs are barely moving also.

Record bar is always in the signal path, have you cleaned it ?.
In some boxes, line-in doesn't have a dedicated position at the source selector, but when you plug a cord, the RCA jack has an internal switch that disables the actual source and feeds the amp with the external you have put ... Have you checked and cleaned line-in jacks ?.
Vu-Meter are at preamp level, and before volume control. If they don't move, signal is not reaching the volume/tone control board, perhaps the amp stage works fine.
In order to test amp, you need to set the volume control to max postion. Then touch with your finger the volume knoov pins. You should heard a loud hum.
Another thing, some boxes has an internal regulated voltage for some circuit section like preamp and turner in order to avoid picking-up noise from the supply. Anothers have a ripple filtering. The regulation is acomplished using a transistor. If it's died, many sections of the box will stop working because the lack of power. Can the BBX record from radio ?.

Pedro.

I have cleaned the record switch and checked the volume pot for faults but it looks OK.
There are no line in jacks, only external speakers and mics.
It won't record anything off the radio at all but when I press the record button the volume goes up a bit. It goes up more when I move the tape selector from normal to CrO2 position (with the record button pressed) but it's crackly and distorted. When I press the dial light as well it goes up even louder lol!!

Looks like a non-working preamp.
Do you have any circuit ?. Could you read the IC part used in the preamp section in order to find out which pin is the supply voltage. Perhaps some regulator has died and no power is delivered to the preamp. It's easy to check if you have the circuit with the marked voltages.
Parts from Sanyo starts with "LA". Look near the record bar ..

Thanks for your help Success.
I don't have a circuit diagram for this model so I cannot check it. This sounds too technical for me I'm afraid.

when you heard the static, you might have blown the cones. do you smell a melted plastic smell?

No plastic smell, the speakers are fine.
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