electro 4D random note stutter issue

[groover]

Hi guys,
Last night at my gig my Electro 4 was doing some strange things. Every now and then on the right hand side of the keyboard a note (not necessarily the same note every time) would play again after i'd played it (or still have it depressed), but at full velocity and stutter and fade off. Hard to describe properly. And I noticed one note stop working for a bit (or be quiet enough that i thought it wasn't working), i kept pressing it and it came back. This is really weird. I've owned an electro 2,3 and 4 in my time, been a nord user for 7 years and not seen this before. At first i thought it was the "note stuck at full velocity" problem that i've had before and learned how to fix myself, but this was much more than that. Because it was on random keys and because of the stuttering (echoed note at full velocity that would get cut off then come back then cut off etc as it faded away), i'm thinking its not a mechanical problem but possibly a circuit board problem. I live in Broome Western Australia where its very humid, which i'm sure isn't the best environment for electronic keyboards. I'm thinking of pulling it apart and just spraying the boards with contact cleaner and compressed air and hoping its just a bit of gunk. Anyone have any thoughts on what this problem could be and if i should try spraying it to clean it?
Cheers

[groover]

Hi guys,
Just wanted to see if i could get some opinions on whether i should be safe spraying the circuit board with contact cleaner and then a compressed air can, just in case theres some dirt or dust sitting on the board giving me this problem. It was suggested to me by a friend to do this, but i'd like to get some more opinions before i spray anything on the circuit board. If you're knowledged in this area please let me know what you think.
Thanks

[Mr_-G-]

If you search the forum, you will soon realise that one note sounding very loud is perhaps some dirt in the contact of that key. This is not uncommon.
There are a few tutorials on how to dismantle the various models and clean the keyboard, but whatever you do, I would suggest NOT to use any contact cleaner. These are carbon contacts on some silicone bubbles (like in tv remote controls). Many keyboards use this system and they tend to get dirty eventually.
To clean the contacts, some people use isopropyl alcohol, some others wash them in water (!) with very little soap, rinse and let them dry thoroughly and some just use an air blower. I do not know enough to suggest which one is best, but Pablo might have some useful comments. Sometimes the contacts wear away and need replacing.
Also, it might be better to send it to some service if you are not exactly sure on how to go about it as it might end up in an expensive experiment.

[groover]

Thanks for the reply. But i have had the one note sounding loud (full velocity) problem happen to me about 5 times since i've been playing a Nord keyboard. First time i sent it away, but after that i found a great tutorial on fixing this and have fixed it myself from then on every time. This problem is not that, it has similarities but..
1. It was not the same key every time
2. I played my note and then after i had played it (and heard it) it repeated the note back to me (like a delay effect) at full velocity then cut out and came back then cut out and came back, as it faded off.
3. One note stopped working all together. I hit the note a few times and it came back. (not the stuttering note)
I wasn't planning on contact cleaning the carbon key contacts (in the past I have just blown compressed air over them and fixed my full velocity problem every time). I was wondering if i could spray the keyboards circuit board in case there was dirt or something on there which might be causing this issue. Because the sound was 'stuttering' and repeating i assume its more than a 'dirt under the contact' issue. Because my knowledge is limited, i'd like to see what you guys think before i send it off for a costly repair job which will leave me without a keyboard and unable to gig.
And where i live there is ALOT of moisture and humidity in the air at this time of year which isn't good for electronics. I'm wondering if this might have something to do with it also.
Thanks for any advice you have to give, it's much appreciated.
Cheers

[rb4u1]

I had a similar issue which turned out that some of the sounds would retrigger because I had set the keyboard in high trigger mode.

[groover]

I would NOT recommend spraying circuit boards with contact cleaner. Sounds like a real bad idea to me. Clean connection/contact surfaces yes. shoot into pots or 1/4" receptacles to clean them, okay, but not whole circuit boards.

Not sure what's happening there, but this is not a commonly reported failure mode -- I've never heard symptoms quite like that. Generally speaking, when keys are exhibiting any really strange behavior, the scanning IC is a prime suspect. Could possibly be keybed ribbon cable or socket connection for same, especially since you've had it apart several times already... Best to see a tech with that one, I think.

Bless,

Pablo

[groover]

Thanks Pablo,
I won't be spraying the board with contact cleaner then. I might give t a blast of compressed air tho.
I just plugged my nord in to check the problem,and its refusing to do it now, but it wasn't constant at the gig so i'll keep testing it.
But i again had that missing note right up the top end. After i played the note repeatedly it came back (just like at the gig). Could this be a symptom of dust or something on the carbon contacts under the rubber strip? I've only had notes on full velocity when dust get under these, never had a note disappear. Should i clean the carbon contacts on this note? I only ever blow them with the compressed air can but its worked for me every time i've had the full velocity problem.
Thanks for any advice

[groover]

yes, I do suspect that dust/dirt is the problem with that one note...the stutter thing is a mystery to me, though

bless,

pablo

[groover]

I think its gonna have to go to a tech. I've been sitting here playing it and its done the repeated full velocity stutter a couple of times, but when that note disappeared again i noticed that there was 3 missing notes (in 3 different octaves, not the same notes either, maybe an F, G and an A). When i repeatedly pressed one of them till it came back (as i'd previously done) i found that they all came back together. Which makes me think its not dirt in a contact but some other issue. Weird to have more than 1 key affected the same way?

[groover]

Ok this will probably be my last post about this issue until i have some insight to share about its cause.
After pulling it apart and spraying it with compressed air its still doing the same thing. This last time the notes have disappeared they don't seem to want to come back no matter how many times i press them. Its 4 notes that disappear together, (in this order), A (after middle C), F, C#, and high A. Doesn't matter if i use the octave shift or transpose, its still the same keys gone. I now believe the stuttering may have been when the key kicked back into life (albeit at full velocity) after disappearing, and cutting out again and coming back repeatedly as it struggled to keep working.
My last question before i send it to a tech is:

It can't be a contact issue if 4 keys from 3 different octaves are involved together can it? They all stop working together, and when they come back its together also.

Any thoughts are much appreciated.
Thanks guys