Humming and popping but only at first

How to Stop a Subwoofer Hum - HowStuffWorks

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Would you like to learn how to stop your subwoofer from making a consistent low-frequent hum or buzz? Read this article to learn how to stop a subwoofer hum.

You have a short. This is either from a bad cable or a faulty price of gear.

to find the problem do you want to isolate pieces of the system. Turn on just your speakers (if they're powered) or amps (if the speakers are not powered). With the mixer off, if you were getting a pause the short exists after the mixer. No buzz? Great! Turn the amps or speakers off to prevent popping. Turn on the mixer, and then turn on the speakers or amps. If you have a bus now with all channels on the mixer down it is likely your mixer. If there is no buzz, Bring the channels up one at a time. Once you find the buzz, turn the channel back down and plug unknown working microphone and cable into its channel. If the Mike buzzes when you bring the channel up it's the channel on the mixer. If it does not then the issue exists before the mixer. This is most likely and also the least expensive to resolve. Check the snake if you have one and all cables in line in a similar fashion. Most likely a snake channel has failed, you have a bad cable plugged in the snake Or you have a bad DI box or mic plugged in.

Happy hunting

Is it a factory amplified system? Could be the volume knob. Might try unplugging the radio for test purposes and see if it still pops and buzzes to get a better idea of where to go next

Hello,

Right click on the task bar --- then select 'properties' ----- In the task window, click on the 'Customize tab' ----- Now select the icon for your X 530 Speakers and set its status as 'always hide'.

This should avoid the popping up of the speaker icon.

Please let me know if this does not work for you.

Regards,
Aby

Ground Loop Isolators are nice, but if you want truly crystal clear sound, you will need to run a common ground. All electronics will need to be run close to the amp, as more than about 3 feet of ground wire from the amp can cause sound issues. When I ran my common ground, I connected my radio and satellite together, and ran one sigle ground wire to the backseat of my car, where the amp grounds are located. This will optimize the clarity of the sound coming through the speakers. For the popping sound in the speakers when the car is powered on or off, you need to see if the radio itself has a wire to power the remote connection on the amp. Most of the time, they will, and this is the wire you will use to turn on the amp itself, as it delays each item powering on and reduces the chance of popping in the speakers. DO NOT run the remote wire from the amp to the accessory wire of the radio, as this will cause the popping sound you are hearing. If the radio does not have an Amp Turn-on wire, then you may need to improvise by using an accessory wire in another location, but even this is may cause popping as well. The pop comes from multiple things turning on at once, so the Amp Turn-on wire delays the amps for just a moment, preventing the pops.

WHEN THERE IS A BUZZING NOISE IT MEANS THAT ONE OF THE INTERNAL COMPONENT HAS FAILED .RANGING FROM A SMALL DIODE TO LARGE PARTS LIKE
THE MAGNETRON OR TRANSFORMER OR CAPACITOR. IF IT IS 10 YRS,OLD YOUR BETTER
OFF GETTING A NEW ONE .BECAUSE YOU COULD INVEST MONEY IN THIS ONE AND HAVE SOMETHING ELSE GO TWO DAYS FOR NOW.WITH A NEW ONE YOU ALSO END UP WITH THE NEW WARRANTY. HOPE I HELPED. KEN62 GOOD DAY!

There is a major short somewhere,the hum you hear in the speaker
is the frequency of the DC electricity flowing through the speaker coils,do all four speakers hum or just one?Do you have a stock or aftermarket stereo?

There might be something wrong on the volume dial, or the speaker connection.
SOLUTION: Check the speaker cables on the back.

"Noise", as used in this document, is a general term referring to any sound a speaker system makes that is not part of the original source material. There are many different types and sources of noise, each with its own solution. Below is an explanation of the common types of noise, what causes them, and how to minimize their occurrence.
Hum or Buzz
There are four common causes of humming and buzzing:

1. Sound card If the humming or buzzing gets louder or softer with changes in the volume setting, this is an indication of noise coming from the sound card. In this case, check all of the connections to the sound card to make sure they are all completely plugged in and secure. Then, adjust the level setting of the sound mixer to obtain the best performance. Generally, you should leave your CD volume settings in the mixer at full and reduce the sound card's master output level down. For information on doing this, please refer to your sound card manufacturer's documentation.
2. Unused input cables If you are not using all of the source inputs to your speaker system (such as using a 5.1 speaker system with a 4 channel sound card), the unused input cables will pick up noise. The solution is different for each speaker system, as described below:
   Z-540 / Z-560 (2 channel sound card): Depress the M3D button.
   Z-640 (4 channel sound card): Depress the Matrix button.
   Z-680 (2 or 4 channel sound card): Disconnect the unused input cables from the control pod
3. High-power devices If you are using other high powered devices on the same electrical circuit, they may be causing hum or buzz. If so, discontinue their use while you are using your speaker system. Examples of such devices include microwave ovens, halogen lamps, power tools, etc. Also note that high-power devices with dimmer switches (such as halogen torchiere lamps) will cause an especially pronounced buzzing effect. To minimize hum or buzz, make sure that the dimmer switch on these products is either all the way on or off.
   
4. Electric Polarity In many countries, the US being one, the electrical power grid is polarized. In these countries, the power plugs are designed so they can only be inserted into the wall socket in a single direction. For example, in the US one of the plug blades is larger than the other. To avoid humming and buzzing, both your computer and speaker system must be properly plugged into polarized outlets. If your wall outlets do not have polarized plugs, as in the case of many older homes, and you are using adapters to plug these power cords into the wall, it is possible that the polarity of either your computer or your speaker system is reversed. In many other countries, such as most of the European continent, wall sockets are not polarized at all - making it even more difficult to properly match the computer and speaker system. To solve the problem you will need to remove the power plug from the wall outlet, rotate the plug 180°, and re-insert it into the wall. Try this for your speaker system power cord, your computer power cord, or both. You should be able to find a combination that will eliminate the humming and buzzing.
   

Pops and Clicks
There are three main causes of pops and clicks:

1. Sound Card Many pops and clicks are created by the sound card. There are two common causes: sound card quality and older or mismatched drivers. If the overall volume level of the pops and clicks goes up and down as you change the volume on the speaker system, the noise is being generated by your sound card. Lower quality sound cards don't include the necessary circuitry to cleanly remove noise from the sound output. Logitech's higher-powered systems, such as the Z-560 and Z-680, are also sensitive to the overall quality level of the sound card. If you are using an older or lower quality sound card, we suggest upgrading your sound card. The other primary cause is older or mismatched drivers. Make sure you are using the latest drivers for your sound card.
   
2. Multi-tasking If you are running more than one program on your computer that accesses the sound system at the same time, small pops and clicks can be common. This is a function of your computer and/or sound card. A common example is using a program that generates occasional audio feedback (such as beeps or other sound effects) while listening to an MP3 track in the background. The solution is to turn off audio feedback in the first application so that the background MP3 track is uninterrupted.
3. Interrupts in the Digital Bitstream On digital systems, such as the Z-680, it is normal to hear a very faint "tick" when you switch between inputs (by pressing the input button). You may also hear louder 'clicks' or 'pops' on a device such as a standalone DVD player or a sound card if it is plugged into one of the digital inputs. On some systems, this noise may occur when skipping tracks, switching audio streams (for example, from Dolby Digital to DTS), or navigating a DVD menu. The clicks and pops occur because the device is sending out an interrupted digital data stream. This behavior generally occurs with older software and older players, but is uncommon on most modern equipment. The Z-680 has been extensively tested with the latest sound cards, software DVD players, and standalone DVD and CD players. If you experience extensive popping and clicking, we suggest upgrading to the latest version of your software DVD player or, if using a stand alone device, trying a different speaker model. If you need more assistance with this issue, please contact Customer Support.
   

Stutter
A stuttering sound track is an indication of either insufficient or conflicting computer resources. Check to make sure that your computer has sufficient processor power and memory to handle the applications you are running, especially if you are using a software DVD player. Defragmenting your hard drive may also help. If you are sure you have sufficient resources, check to make sure that you don't have any conflicting IRQ or DMA channels.
We have also seen some software DVD player/sound card combinations that cannot properly output a Dolby Digital or DTS signal through the sound card's S/PDIF digital connector. (S/PDIF is a generic term for either coax or optical digital connections.) The result, when using a Z-680 hooked up to a S/PDIF connector, is a stuttering soundtrack. As mentioned, this stuttering is caused by the computer, not the Z-680 speakers. Switching the software DVD player's sound output to the 5.1 analog outputs will generally solve this problem.
Hiss
All high-powered amplification devices - everything from multimedia systems to home theater systems to movie theater sound systems -- generate some level of background noise, or hiss. In addition, low quality sound cards with poor signal-to-noise ratios can generate a significant amount of steady hiss that is reproduced on the speakers. Under normal conditions at a normal listening distance, the hiss coming from the sound system should not be noticeable. In a very quiet room, or if you place your ear very close to the speaker, you may hear a very low level hiss. This is normal, but should be completely masked by normal music and game sounds.
If you find that hiss is noticeable, it is likely that the speakers are too close to your listening position. If the speakers are too close, you will not obtain the best imaging of the sound and you risk damage to your hearing when the system is playing at full power levels. Try moving the speakers further away from your normal listening position. We recommend at least 18" for the moderately-powered systems (such as Z-340, Z-540, and Z-640) and at least 30" for higher-powered systems (such as the Z-560 and Z-680).
Also, note that the satellites in most Logitech speaker products are designed to be wall-mounted. Wall mounting the speakers provides two benefits: 1) it moves the of the satellites further away from your listening position, making any hiss less noticeable and 2) it moves all of the satellites further away from each other, providing better channel separation and surround sound spatialization.

It sounds like a capacitor in the power supply is just about to die. With the power disconnected have a look at the large tin can looking gizmos near the power transformer. There could be a couple of them. Leave the unit switched off for a while before going near them they could still pack a splat. Replace them with the same value and make sure they're connected the right way and it should solve your problem. Whilst in there have a good look for any other smaller capacitors which look as if they're getting rounded at the top. Replace them too. Either that or dig deep and buy a new one.