3.5mm port emits noise when M17x plugged in to power

Hey there guys.

I have an issue with my M17x's audio port (3.5mm) which emits a very faint noise on plugged in speakers/headphones when I'm tethered to a power source. It's a faint hum that increases as I pump up the volume on my speakers or headphones to the point where it gets very loud and noticeable. I own a pair of Audioengine A2's (which are fantastic speakers btw) and I have never had this issue with any other devices but I have to dial down to 35-40% volume on my A2's to compensate for the annoying hum I get from the M17x.

This hum is not present when the laptop is on battery power, so there's definitely something going on with the power brick. I decided to post here (it's been a while!) hoping that at least one of you have noticed this issue and rectified it. I DJ at small parties sometimes and this hum seriously ticks me off. I would stay on battery if not for the dismal battery life in the first place. My only other option is Optical but I its a hassle getting a good quality DAC and hooking it up all the time. I'm also on a college student's hard-earned budget lol.

So does anyone have any suggestions/workarounds? Could this be a grounding issue (I'm pretty my college dorm room is well grounded)? I'm considering buying an external USB soundcard but the M17x already has one and I don't want to have to buy one when I technically have something equally capable installed on my machine. Any thoughts?

 

No one, really? Aww man.

I'm looking at the possibility of using the Optical output + a DAC like the audioengine D1, and then connecting this to the speakers. However this is going to burn a hole in my pocket and I'd much rather not... And just throwing it out there, does anyone know from personal experience if RCA works better than 3.5mm? I've personally never really noticed a difference, although I have never own higher-end audio gear until now.

 

I get this static low hum from my R2 constantly, even if its muted, increasing volume does increase the hum a tiny bit though. This happens only with headphones or external speakers.

I have had dell replace motherboard and IO-board but it didn't resolved the issue at all, In the end, I resigned to blue tooth headphones and all is well now

 

Do you guys have the microphone-in muted? On most systems it seems like that adds a hiss (although come to think of it, it might not play through the audio by default...)

I know I returned an M15x a few years ago because of noise though :-/ Hope the M17x isn't still doing that.

Maybe Creative still makes a USB sound card?

 

Yes, nkdv, the problem you're describing is called a "ground loop." Here's an explanation of why it occurs and possible ways to fix it:

Ground loop (electricity) - Wikipedia, the free encyclopedia

Basically, what it usually means is that you need a stronger ground connection between the laptop's audio signal ground and your powered-speaker's/audio-amplifier's signal ground. It can be the fault of the audio cable itself, particularly if it's a long or cheap/thin cable. So, a shorter, thicker audio cable with heavier shielding will often help.

Also, I'll often attach washer-like terminals to screws (that screw into the metal housing or into connector shields) of the two pieces of equipment, with a heavy-gauge wire soldered between those two terminals (DON'T SOLDER THE TERMINALS WHILE THEY'RE SCREWED INTO THE EQUIPMENT, AND DON'T FORGET TO DISCONNECT THE WIRE BEFORE YOU PACK UP YOUR EQUIPMENT!). But you have to first make sure that the screws are connecting you to the signal grounds, and not some other isolated electrical ground (connecting instead to this can burn out equipment!), which you can usually determine by inspection -- look to see if the screw hole is directly connected via metal to the audio connector's ground. So you do this at your own risk.

One other possible solution is that, if any of the equipment uses "unpolarized" AC plugs (i.e., if you can unplug the power cord, rotate the plug 180 degrees, and plug it back in with no problems), then sometimes just rotating an AC plug can solve the problem. I recommend doing this ONLY while ALL the equipment is turned off.

I should also mention that if you're getting it through headphones that are plugged directly into just your headphone jack and not connected to anything else, then that would imply an INTERNAL ground loop, which would be a laptop design issue. I just ran some tests with that configuration with max volume on quiet audio passages on my M17x R4 and didn't hear any hum. But I would need to try it with some headphones with more bass response than I have handy, to be absolutely certain. If a hum did exist in that configuration, then an opto-isolator connected to the headphone jack presumably wouldn't fix that.

Note that the Bluetooth 4.0 audio output of the M17x R4, if you use an apt-x receiver adapter, is of very high quality, and may avoid the problem. You could try it with the laptop and any Bluetooth-audio-receiving device first (apt-x or non-apt-x), and that should tell you if it fixes the problem. If so, then you could go with an apt-x-capable Bluetooth receiver for improved audio quality. If you take the Bluetooth approach, then you might carry an audio cable as emergency backup. Here's an apt-x-capable Bluetooth adapter that's highly-rated and should work with the M17x R4:

Avantree Saturn Bluetooth Audio Converter Adapter Transceiver, Featuring A2DP AVRCP apt-x CSr

I wouldn't count on charging-it-from-the-computer/using-it-at-the-same-time, because then you may be back in ground-loop territory (particularly if you use a cheap/thin/long usb cable, with little shielding, for charging). So you might have to charge it up ahead of time, or find a separate usb charger that doesn't introduce a ground loop with your speakers/amplifier.

Good luck!

 

Yeah so you get static noise... everybody gets static noise it's electromagnetic in nature so any cable that transfers electicity will have it... use optical out if you are so bothered by it (you will never get a clear sound from your speakers because they have a Jack connection.

 

Most notebooks do NOT get static, unless the volume on the line in is not muted. I'm wondering if this is actually a design flaw on the M17x given I've already returned an M15x for it...

Qfoam sounds like yours does NOT have it though, so that's good.

 

I have long farting sound always after powering down my m17x R2. Between 10-15 minutes after power down and it lasts around 3 seconds. Think It have something to do with discharging capacitors.

On a side note I really recommend you getting external, dual channel sound card. Only then you can DJ since this will allow you to cue tracks via headphones instead just playing them like you do right now.

 

So, happily, the laptop doesn't fart while you're using it.

 

Have a look at this thread to see if you can implement any changes that might rectify your issues: http://forum.notebookreview.com/ali...-all-different-noises-finally-resolution.html - there is a suggested fix for the following problem quoted below, which sounds similar to what the OP is experiencing:

Might help out - if not, nothing ventured - nothing gained.

 

I think that one is only with the computer off but it does seem like this issue. Haven't heard of that issue before but I know that static can be caused by anything. Have you tried the computer on any other place plugged in?