Kronos Screen Not Responsive. Korg Service Center Can't Fix

[schez]

I have a Korg Kronos 88 key 1st Gen with the latest OS 3.0.3

The screen will not respond to any finger or stylus touches, physical faders and knobs on the left side do not work, sustain pedals will not respond, all other buttons and scroll wheel works. Occasionally there will be moments where everything is fully functionally, then shortly after will go back.

I updated the OS and restored when it had a moment of working and that seemed to fix it for a few days, then right back to it. I took it to an Authorized Service Center and they could not figure it out because it worked fine the whole time they had it. They thought it could be the power cable and suggested getting a new one. I got a new one and the Kronos was fully functionally for a day or two but now is back randomly not working. Though it seems to work for longer than before. Also I have it plugged into a furman power conditioner. Could it still be a power issue? Maybe my house has bad power and that's why it worked fine at the repair shop?

Sometimes I connect an M-Audio Oxygen 49 1st Gen via USB to play more sounds. A couple times when connecting the MIDI controller when the Kronos was working made the Kronos freeze up. But there have a plenty of times when it didn't make a difference.

When the freeze up happens while the Kronos is working and I'm in combination mode, the first Timbre will pan hard left. Not sure what that means.

[Bald Eagle]

If you are suspecting a power problem then a power conditioner may not be helping much. They generally protect against surges and spikes. They don't do anything for under voltage or other types of problems. They are really just glorified power strips. You may want to consider a voltage regulator or even better a UPS.

Power supply problems can produce strange results but who knows, your problem could be something else.

[Rosen Sound]

If your unit is in warranty i would demand a replacement.

[schez]

If you are suspecting a power problem then a power conditioner may not be helping much. They generally protect against surges and spikes. They don't do anything for under voltage or other types of problems. They are really just glorified power strips. You may want to consider a voltage regulator or even better a UPS.

Power supply problems can produce strange results but who knows, your problem could be something else.

I will look into that. I was thinking about getting a UPS anyways for live use since it takes so long to restart the Kronos when power goes out. Do you recommend any specific brands of UPS or voltage regulators?

[geoelectro]

I have a Korg Kronos 88 key 1st Gen with the latest OS 3.0.3

The screen will not respond to any finger or stylus touches, physical faders and knobs on the left side do not work, sustain pedals will not respond, all other buttons and scroll wheel works. Occasionally there will be moments where everything is fully functionally, then shortly after will go back.

I updated the OS and restored when it had a moment of working and that seemed to fix it for a few days, then right back to it. I took it to an Authorized Service Center and they could not figure it out because it worked fine the whole time they had it. They thought it could be the power cable and suggested getting a new one. I got a new one and the Kronos was fully functionally for a day or two but now is back randomly not working. Though it seems to work for longer than before. Also I have it plugged into a furman power conditioner. Could it still be a power issue? Maybe my house has bad power and that's why it worked fine at the repair shop?

Sometimes I connect an M-Audio Oxygen 49 1st Gen via USB to play more sounds. A couple times when connecting the MIDI controller when the Kronos was working made the Kronos freeze up. But there have a plenty of times when it didn't make a difference.

When the freeze up happens while the Kronos is working and I'm in combination mode, the first Timbre will pan hard left. Not sure what that means.

I would suspect a connection problem with the left control panel. It's possible the display touch screen and left panel have a common data or power source. If you're comfortable you might check the internal plugs and cables. Seems like the service center would have done that but if it didn't act up for them it might not have been done.

Of course, if under warranty it should be repaired by an authorized service center. As a tech myself I would at least do this check. It's somewhat common on instruments that travel.

Geo

[schez]

I would suspect a connection problem with the left control panel. It's possible the display touch screen and left panel have a common data or power source. If you're comfortable you might check the internal plugs and cables. Seems like the service center would have done that but if it didn't act up for them it might not have been done.

Of course, if under warranty it should be repaired by an authorized service center. As a tech myself I would at least do this check. It's somewhat common on instruments that travel.

Geo

That would make a lot of sense. A couple yrs ago the Kronos was dropped and I had to get a new circuit board, faders, and knobs for the left side. Maybe this repaired area is causing the issues. And yes this Kronos has traveled a lot in the last few yrs. I might take it back to the service center and have them check that out, or possibly take a crack at it myself. Thanks a lot!

[SanderXpander]

I'm not an expert but APC is a well respected and often recommended brand for UPS units. I've used one myself for a few years now with no issues. The Kronos itself really doesn't really draw that much power so don't go for the huge industrial ones, the smaller models are heavy enough as it is.

[AntonySharmman]

schez
This issue has nothing to do with UPS or any power issue , it's a hardware issue and probably a screen carbon connection issue
that can't be approached by a simple user and must handled only by authorized service (mostly replacing your screen) !
Temperature mostly determines carbon discontinuing contact but soon this issue will be obvious even in service center.

[Bald Eagle]

If you are suspecting a power problem then a power conditioner may not be helping much. They generally protect against surges and spikes. They don't do anything for under voltage or other types of problems. They are really just glorified power strips. You may want to consider a voltage regulator or even better a UPS.

Power supply problems can produce strange results but who knows, your problem could be something else.

I will look into that. I was thinking about getting a UPS anyways for live use since it takes so long to restart the Kronos when power goes out. Do you recommend any specific brands of UPS or voltage regulators?

I always use APC UPS systems. Never had any issues with them.

[ronnfigg]

I had a very similar circumstance years ago with an older piece of analog equipment. It would intermittently exhibit some very peculiar behaviour. When I took it into the shop they could not duplicate the problem. But when I would be using it in real life situations the problem would arise. So one day as I was wheeling it out on a two wheel dolly I decided to take a good bounce on the threshold of a doorway I was going out. The next time I fired it up it was constantly exhibiting the peculiar behavior. I took it to the shop and they had located a hairline crack on the power supply printed circuit board. What was happening is that as the unit heated up the traces would separate causing circuits to malfunction. I guess by me jamming it over the doorway threshold made the crack big enough so they could see it. They were finally able to repair it. Since you say the physical controls portion of your Kronos was repaired recently is quite probable they missed something that may have been broken, but not visual to the naked eye. You might want to take it back to that shop and see if they can figure out whether or not they missed something.

[SeedyLee]

Code: Select all

Korg Forums Troubleshooting Flowchart

+-------------------------+           \   +-----------------+  
| Kronos has inexplicable |   ---------\  |    Use a UPS    |
|        problem?         |   ---------/  |                 |
+-------------------------+           /   +-----------------+

[danmusician]

schez
This issue has nothing to do with UPS or any power issue , it's a hardware issue and probably a screen carbon connection issue
that can't be approached by a simple user and must handled only by authorized service (mostly replacing your screen) !
Temperature mostly determines carbon discontinuing contact but soon this issue will be obvious even in service center.

How does that explain knobs and buttons not working?

[AntonySharmman]

How does that explain knobs and buttons not working?

Read carefully schez description ... he's talking about screen's touch layer surface response and I just wrote the cause !

SeedyLee ... +1 , but you can also add a variable in equation , J="Reload OS"

[danmusician]

How does that explain knobs and buttons not working?

Read carefully schez description ... he's talking about screen's touch layer surface response and I just wrote the cause !

SeedyLee ... +1 , but you can also add a variable in equation , J="Reload OS"

Reading carefully, he also says "physical sliders and knobs."

[ronnfigg]

Once again, since schez said the unit was dropped and he had repair work done to it, I would recommend that he take it back to that repair shop and have them inspect their work. They may not have caught something or in the reassembly they have missed something. Giving them all of the current symptoms may direct them to a faulty component and/or connection. That was part of the problem I had with that old analog unit I took into the shop. I had only giving them one symptom. If I had given them the multiple symptoms that were going on they could have traced it down a lot quicker. If you are still under the repair shop's warranty I would recommend taking it back to them. Obviously it's an original Kronos so you are out of Korg's warranty. Korg tech support might also have some thoughts on the problem. Try contacting them.