Helix LT static cutting in and out

[marmatkat]

Hi Folks,

 

My 2017 LT is acting up recently, and I could use some advice. It's making a static sound that cuts in and out, regardless of whether my guitar volume is at ten or zero. (I hope you can play the two attached sounds files.) There is no static if the guitar cable is not plugged into the input jack. Rebooting doesn't solve it, but it does act somewhat differently each time (one time I got no output at all). The tuner shows intermittent bars, which makes me think it's an input issue.

 

Edits:

• The problem is not present when I plugged into a return (thanks to Schmalle for the tip!)
• The guitar input jack is not loose.

 

I've tried different guitars and cables, with no difference, and I've tried headphones, 1/4" mono out, and AES, with no difference. I found the discussion Helix input cutting in and out (esp. this post by mmk2828) that talks about a possible cause being a circuit board that's attached to the input jack, so I might try taking it apart and having a look, but I thought I'd ask if anyone else has had this problem and solved it.

 

My next gig is a week from Saturday thank goodness, which gives me time to buy a new one if necessary ($$).

 

Thanks!

Guitar volume up.m4a Helix guitar volume 0.m4a

[Schmalle]

Sounds like something is wrong in the input hardware.

 

Does the problem appear if you choose one of the returns as input source in the input block?

[marmatkat]

On 10/25/2024 at 3:38 AM, Schmalle said:

Does the problem appear if you choose one of the returns as input source in the input block?

 

The problem is not present when I plugged into a return. Great debugging tip!

 

Note: I didn't know you could plug a guitar into a return. I found the post helix two guitars I read "But you don't have the Auto-Z functionality" and that an input buffer might be important (I've never owned one, or frankly understand the need).

[Schmalle]

Ok, seems likely that the input jack has a loose contact.

 

At least you have a workaround with the Return until you fix it. You don't need an extra buffer. Just make sure to set the relevant Send/Return to INST (not LINE) in the Global Settings -> Ins/Outs . That makes it a normal instrument input with 1 MOhm impedance.

 

And yes, using a Return as input bypasses the Auto-Z feature but for the most part Auto internally sets the impedance to 1 MOhm anyways.

[theElevators]

Try cleaning the jack with liquid DeoxIT.  I've had MANY such issues on all sorts of amps, guitars, keyboards where the input jack would start cutting out.  Cleaning it with this wonderful stuff always did the trick.  Hopefully that will do it, and it's not some soldering issue inside.  But you could take your Helix apart and check it out if this doesn't help... OR just keep using Return1, and forget about it.  I think the auto-impedance doesn't work with it, but everything else, including the tuner will work. 

[marmatkat]

On 10/25/2024 at 10:22 AM, theElevators said:

Try cleaning the jack with liquid DeoxIT.

 

Thanks for the suggestion. I have some, but can I just spray it into the hole? I think it won't damage the circuitry if I spray it in. ?

[theElevators]

Take a 1/4" cable, put contact cleaner on the jack.  In-out-in-out, twist, etc. 

[marmatkat]

On 10/25/2024 at 12:18 PM, theElevators said:

Take a 1/4" cable, put contact cleaner on the jack.  In-out-in-out, twist, etc. 

 

Did not fix it, but it was worth a try. I suppose the next step would be to disassemble it. I found a number of videos and posts, and it seems like the LT is slightly easier to take apart. Will take a some courage, though.

[marmatkat]

Well, I took the back cover off and found that the LT doesn't seem to have that same "guitar conditioning circuit" board attached the the guitar input jack. Instead all I saw was the guitar (and two return) jacks covered with small metal boxes (term?) (In the image, the lower right box is the guitar one.) I don't see the point of detaching the board from the back of the unit where the I/O jacks are because there's nothing I could do unless the problem is inside the little box. I.e., I'm guessing it's a circuit board problem and not a jack one?

 

I'd really appreciate your thoughts on this. O/w I think I'll use a Return input for now until I can send it in for repair. Or buy a new one and use this one as a backup once it's repaired.