QC strange power down and reboot issue during a gig- 'DRIVER NULL' error in the logs

CorOS 2.0.3 1.x

**During my first gig with the QC it has suddenly rebooted itself. During a song I have noticed that I have no sound, I looked down and the screen was dead while the knob lights were on. After few seconds the unit started the reboot sequence. After the booting sequence it behaved perfectly normal. You can imagine its very bad situation for a guitar player to stay on the stage in the middle of a song with no sound at all. It’s a new device not even 2 months old and this happened for the first time.I was using the original power supply and not me or my bandmates have noticed any power fluctuation or outage. Other devices were running perfectly normal (mix, amps, computer etc.)

I have contacted the support and send a report directly from the device and asked if they can tell me what caused the reboot. Are is they reply:

There is a ‘DRIVER NULL’ error in the logs, which could translate to several possibilities, which is why the repair engineers need to inspect and repair your unit. Once they have your unit they will be able to diagnose exactly what is wrong.

We would like to retrieve your unit for inspection and repair at our service centre. Keep in mind that the whole process shouldn’t take more than a couple of weeks.

Please, send us the following information:

  • Name
  • Email
  • Phone
  • Shipping Address
  • Quad Cortex’s Serial Number
  • Quad Cortex’s CorOS Version
  • Order Number (or PDF invoice)

Well I can’t stay without my effect device for few weeks so I have decided to further test the device…but I am disappointed to experience such problems with new device (not even 2 months old). I think such expensive device like QC should be also reliable. I’m also disappointed that they claimed that based on the logs they can not even tell me if it a hardware or software issue.

Anyways I just want to let you know about such issue and maybe there are more of us affected by it. If anybody has a suggestion I’m thankful to read it.

Korny from Slovakia **

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If NDSP has requested the unit to diagnose and repair etc., that is the process and ultimately what will resolve your issues. There are multiple variables and the logs are just more information to help with the overall diagnostic process.

Personally, I have only really heard of this occurring due to using alternate power supplies with inadequate power resources but again, there are multiple variables. I am assuming support sees something in the logs that warrants closer examination of your QC. It’s good that you contacted support, they have logged the issue and are pursuing resolution requiring the unit. I agree, it’s always disappointing when you need to send something in for service but that is the process and hopefully its resolved quickly.

I have used only the original power unit. I have gigs planned for all summer so its not an option for me to send the unit to the service center for several weeks without replacement. I have decided to test the device further more. Until now it seems to work normal, but if the issue repeats i will be forced to return it to the seller or have it replaced there. It will be probably quicker. But you are right I am really disapointed thet i can not relly on the unit on stage…

I have to say that the support was very polite but they coudn’t tell from the logs if its hardware or software issue and the offered solution to send them the device just doesnt solve my situation. I hope this doesn’t affect too many people, especialy during gigs like it happened to me.

I will keep you posted if the issue occured again or everithing is OK and it was one time joke:)

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I feel your pain. Why is it that, if there is a gear problem, there is an 80% chance that it won’t reveal itself until you’re at a gig? Damned Murphy’s law!

That being said, what you described could also be caused by something as simple as a loose power connection, split-second power failure or even low line voltage. I’ve played plenty of venues with weak, sloppy or even burned power outlets on the stage and plenty with low line voltage. Analog gear can often handle these issues without much trouble but digital gear can exibit anything from errors to full shut-down.
Since it has only happened once and being without it is a problem, I agree that you should continue to use it and see if it happens again. Just bring a back-up processor or amp, if you can. Also, use a quality power conditioner for all gear, especially for digital gear.

Just like reading problem codes in your car, a diagnostc system can only provide a limited amount of information. I don’t think most guitar processor have this capability at all, let alone connecting with the manufacturer via the internet. I don’t think any company offers immediate hardware repairs over the internet. :grin:

Hopefully it was a one-time glitch and will never happen again. Please keep us posted.

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Hi. Just wanted to say for your confidence that generally the QC is a robust unit. I’ve had my QC for a year and done over 60 gigs plus a lot of home use and I haven’t had any issues like this.


I have played 80 plus gigs with zero issues. I use a CIOKS DC7 to power my QC, but I also use a power conditioner in front of all my gear.

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