Juno G - No output, no sound issue

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kkd3031
Posts: 2
Joined: 16:07, 4 August 2016

Juno G - No output, no sound issue

Post by kkd3031 »

Hello,

My Juno G does not generate any sounds from any of outputs including the headphone output.
If I bring the volume to maximum level on both Juno G and the keyboard amp, I can barely hear with a huge white noise, but I would say it's almost no sound.

I tried factory reset but it didn't fixed the problem.

Is there anything I could try/check or should I go to the service shop?
In case I need to replace any parts, anyone knows what part could be the one that needs to be replaced?

Thanks a lot!
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Leo Castro
Posts: 139
Joined: 22:58, 17 June 2016

Re: Juno G - No output, no sound issue

Post by Leo Castro »

Hello, it is very difficult to know which part to change without knowing where the problem is. Have you tried if receiving midi data from another device there is sound? Is the local system on? Does the d-beam generate sound? Do the midi sequences reproduce? Is the sound gain within Menu / General / Audio set to 0db or is it too low?
SagaciousB
Posts: 5
Joined: 17:15, 12 May 2015

Re: Juno G - No output, no sound issue

Post by SagaciousB »

Unfortunately it seems my Juno-G ran into this as well.
After not playing it for months, I fired it up, plugged in my headphones, started playing. All was normal, then suddenly I started hearing some static crackling, the volume started cutting out. I thought maybe it was just the headphone jack connection - so I wiggled it, and that helped for all of a few seconds. Crackling, sound coming in and out, until within a minute, the sound completely cut out.

Unfortunately, the line outs also seem to have no sound coming out of them.

I did a factory reset, even though it clearly seemed like a hardware failure. No luck.
Opened up the case, and re-seated all of the wire harnesses. Inspected the jack board - nothing obviously wrong.
It is clear that the keys are being registered as being hit (visible in the display in Perform mode) so its nothing with the keypad.
I called Roland's support line but I guess the parts department is closed due to COVID-19. Also, when I tried to take out the jack daughter card, apparently a bunch of the screws in the back are now stripped from replacing my display. So, I'm not sure a replacement is really going to be that easy. This thing might be doomed to become a midi controller (time for Windows 10 driver adventures) or sold for parts :-(
SagaciousB
Posts: 5
Joined: 17:15, 12 May 2015

Re: Juno G - No output, no sound issue

Post by SagaciousB »

Interesting update: I was having a good time just using my Juno-G as a midi controller with Pianoteq demo (wow, does that sound better than the built-in piano voices!) and after a few hours, thought - hmm, I wonder if the headphone-out fixed itself.
Oddly, it did!!! I was hoping maybe the keyboard just needed some love. Or perhaps enough vibration got something seated into place.
Next day, turned it back on.... no headphone/line-out sound again. But, I decided to just leave it on again for a while. Maybe 30 min later - suddenly there was sound again.
So, this seems likely to be some sort of heat-related electronics issue. Perhaps some bad solder joint? The voltage regulator was pretty hot, but I'd expect if that were faulty then the entire board shouldn't work. Not quite sure what else to check.
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craigsfrost
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Joined: 05:21, 7 March 2018
Location: SF, CA, USA
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Re: Juno G - No output, no sound issue

Post by craigsfrost »

I have had no sound sometimes on startup. Can hear just a tiny bit when cranked all the way up. Shut of and turn on has always fixed it. It's scary though.
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Leo Castro
Posts: 139
Joined: 22:58, 17 June 2016

Re: Juno G - No output, no sound issue

Post by Leo Castro »

craigsfrost wrote:I have had no sound sometimes on startup. Can hear just a tiny bit when cranked all the way up. Shut of and turn on has always fixed it. It's scary though.
Same here, a couple of times. Off and on again, and working good.
kkd3031
Posts: 2
Joined: 16:07, 4 August 2016

Re: Juno G - No output, no sound issue

Post by kkd3031 »

Wow, it has been 4 years since the issue started. I've been able to make the output work by warming it up for about 20-30minutes. However, it has been getting worse and now it’s not usable at all as a standalone synth. It works great as a midi controller, but what a bummer. I’m going to open it up and see if I can find any clues. I’ll keep you guys posted but please comment if you have any ideas that are related to this issue.

At least I've been lucky that I've had no screen issues yet! Fingers crossed!!!
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Leo Castro
Posts: 139
Joined: 22:58, 17 June 2016

Re: Juno G - No output, no sound issue

Post by Leo Castro »

Good luck with that! Maybe the problem is near the DAC, check any cold solder joint.
Paul_D
Posts: 1
Joined: 19:27, 20 October 2020

Re: Juno G - No output, no sound issue

Post by Paul_D »

Hello, bumping this thread for a similar problem. My Juno-G suddenly lost about 90% of its volume recently while I was playing it, on both the line outs and headphone output. I did a factory reset, checked the system settings for volume and gain, that's about all I could find online. Since it cut out suddenly I feel like it's probably hardware, or maybe a solder joint since I was pounding on it pretty hard when it crapped out. It still works and the sounds are fine but they are very faint, maybe 10-20% of the regular volume so you have to turn the board and the amp all the way up to hear it. Not hearing the white noise that the previous poster was hearing fortunately.

I haven't looked inside, I don't know if I'm skilled enough to solder on what I'm imagining it looks like but I'll check it out and see if I see anything obvious. If not, is it worth getting repaired, if it maybe costs $150 or so? It's gotta be 10-12 years old at this point

Thanks for any suggestions!
rrete
Posts: 17
Joined: 09:43, 8 December 2020

Re: Juno G - No output, no sound issue

Post by rrete »

Hi
Mine had R channel dead, with service notes and schematics I found the problem was Vol POT. I think that's the problem. IF THE PROBLEM IS IN ALL OUTPUTS this procedure will help you. This check the way of sound from generator board (MAIN) to outputs
So there is three boards to check better use a scope is recommended, multimeter is better analog . MAIN, where is the processor, memory, etc JACK have external audio jacks, etc and FRONT where vol pot and d-beam are.
If you are sure you can remove rear cover panel (a lot of screws) and is easy to check if MAIN works, find connector cn11(12 wires) is next to rear panel three last pins are 10 L analog out 11 GND and 12 R analog out (sound signals to out jacks/headpones). Put the tip in pin 10 and GND terminal to chassis and hit a key and look at the screen of the scope if image changes repeat with pin12. If there is changes in image in two cases MAIN is OK. If you haven’t a scope or multimeter you can check with two wires to a speaker the sound will be very lower is no amplified I don’t recommend this but if you haven’t tools… (NO SORT WIRES!!!)
This signal go from this connector to JACK panel cn1 (12 wires) and pins 10,11(to chassis) and 12 are the same do it again to check broken wires, this go to cn2 (6 wires) 1 R out 2 GND and 3 L out repeat operation. From 123 pins this signal goto to VOL pot and come back to JACK board recheck pins 4-5chassis and 6-5chassis for L and R signals if works OK if not POT VOL broken and finally is there is no sound maybe IC3 an operational amplifier little chip 8 legs is broken o two capacitors near it (c188 c189).
Hope help you
Steve_Pietras
Posts: 1
Joined: 22:28, 24 January 2023

Re: Juno G - No output, no sound issue

Post by Steve_Pietras »

I think I have the FIX for this!

I too had my Juno-G "fade away"! One moment the sound was present, the next moment it was gone. I DO NOT drag this synth out of my house it just sits on the keyboard stand in my basement. Giving a wiggle to the 1/4 audio out and the sound would get louder for a moment but not fix it. I repair broadcast equipment for a living so I was willing to take a chance on repairs. My first thought was a cold solder joint and I took the board out and re-flowed all the jacks. It didn't help. I next tried cleaning my connector jacks with Deoxit spray, it also did not help. I now suspected coupling capacitors on the Jack board and located the schematics.

I knew the jack cleaning DID NOT HELP BUT when I wiggled the cable in the jack, it would sometimes get louder so something weird was going on with physical flexing / movement of the PCB. Next, I started checking the 100uf 16v and 10uf 16v surface mount caps with an ESR meter.
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Some measured out of tolerance a little one was out 3 ohms. I replaced a few caps in critical areas of the circuits and tried again. Sound was there but went away after a few minutes. THEN sound came back and faded away again (just to make make angry). I took the Jack board back out of the frame.

While working on the jack board the first time, I remembered I had noticed on the foil side (bottom of the board) a piece of foam cushion that was glued down right across the pins of CN2. (the connector is circled in the photo)
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This foam had turned brittle and dark yellow while other foam parts on the back of the jack board were soft, white and pliable. I removed this foam pad as it didn't seem to have much purpose in the spot. (I believe the Jack board might be used by Roland in SEVERAL models so they simply stick the foam pad on to meet the requirements of the production run of several models.) I used a small amount of acetone on a swab to clean the VERY brittle and dried adhesive from around the pins. for good measure, I also re soldered the pins of CN-2.

My JUNO-G is now fully operational again for audio. Headphones, Line outs A and B are all working and NO sound fades. I even performed a 24 burn in test. The next day, Mr. Juno G played with out any audio issues. It has now been several DAYS of power on/ power off cycles and audio has no issues. If I had to do it over again, I would have went with my instinct and cleaned that dried out yellowed cushion pad off first.

If anyone tries this, let me know.

Steve
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