1kHz PC & Speaker Noise - HELP!!!

[dbooth]

Hi guys/gals,

Sandra report to follow....

I've had this problem for a while where both my pc and studio speaker monitors emanate a sawtooth-like 1kHz digital noise when the HDD is doing heavy lifting or even sitting at idol for that matter. The speakers - Yamaha HS-50M's - are connected to an M-Box Mini 3rd Gen, and whilst the sound does not end up in my final bounces inside PT10, it is a constant annoyance & hindrance to me being able to hear the mix clearly.

My set-up:
Win 7 / PT10 / M-Box mini 3rd gen / Balanced ¼” cables / Yamaha HS-50M Monitors

What I have experienced so far...

- Constant sawtooth 1kHz sound (with upper and lower harmonics sometimes) coming from PC Casing when HDD working or mouse moving or clicking on items.
- When speakers are on and connected to M-Box, the sound is amplified through the speakers louder than the general pc noise.
- Upon loading PT, the sound is much worse, then disappears until the session loading screen appears.
- While a session loads, it comes and goes, and comes back fully when the session is loaded.

What I have learned and tested thus far…

- Used a different usb cable to connect m-box (no difference)
- Moved the M-box to different usb ports (no difference)
- Disabled all the usb ports one-by-one (no difference)
- Used unbalanced audio cables to monitors (made it even worse/louder)
- Plugged Shure 840 headphones into headphone socket on m-box front (signal is clean)
- Plugged headphones into speaker outputs on back of M-box – both left and right channels (signal is clean in both cases)
- Unplugged speakers from M-box while still powered (noise disappears / clean signal)
- Plugged speakers into headphone output on M-box (Noise returns as before)
- Plugged power for speakers into separate power plug on wall (no change)
- Plugged power for speakers into the same power on wall as pc and everything else (no change)
- Used same M-box and speakers with Win 7 laptop running PT 8.0 LE connected to power (same noise)
- Used same M-box and speakers with Win 7 laptop running PT 8.0 LE running on laptop battery (clean signal)
- Used same M-box and speakers with Mac laptop running iTunes & Logic X connected to power (clean signal)

My conclusions…

There is some sort of power issue, especially with the USB power. Both the speakers and m-box appear to have no problems per se. They appear to work exceptionally well with a powered Mac laptop & and a battery powered Win7 laptop. The desktop is always powered and creates noise in the system, as does the powered Win 7 laptop, and I have to conclude that therefore this is a Windows pc based issue.

What low-cost measures or tests would people here recommend?

Should I try speaker cables with the ground lifted/removed from the path? Is this as dangerous as a power cable getting the ground pin removed? Are ground loop isolators going to help with this problem, or is this more than likely something caused from the PC power supply at the wall? I’d love to eliminate the pc casing noise too, but at the very least, I want to get rid of the speaker noise, as I can move the desktop to somewhere less annoying.

Also, is there something inside the PC casing that I can check for grounding, etc… and perhaps connect that to the casing of the speakers? How can I find this? What measures should I take?

Am I missing something critical? Please let me know.

Thanks,
Dan

[jeam25]

Wao..good post my friend.... its so well explained and argumentated that make
some Avid personal look so elemental in thier writings BUT.....
Thtas not the topic !! Jajaj

You forgot to tell what plugins you are using if any..if this happens only in protools
or just only at windows home screen ? ( As i understand you said on windows only too but just to be shure )

Altough seems to me a power source issue did you test on another room? Or independent circuit than the current ?

Another thing is changing the mbox driver version..

Hope this help a little ..

[sw rec]

A long shot...the last time I dealt with something like this, it turned out to be insufficient current on USB line. So, even though AVID recommends against it, we put the Mbox (and ONLY the Mbox) on a powered USB hub, and it solved the problem.

[mjslakeridge]

From what you have described, I don't think it is a problem with your speakers, they are probably just amplifying the noise. Since you got a clean signal running on your laptop battery power, but not clean when the laptop was on A/C current, that would seem to indicate a problem with the A/c power. Are you sure no appliances (like a refrigerator) are on the circuit? Or electric motors? You said you plugged the speakers into a separate wall outlet and the problem continued. That wouldn't necessarily solve anything if the two wall outlets were on the same circuit. SW Rec may be onto something with his suggestion.

[dbooth]

SiSoftware Sandra

ID
Host Name : Daniel-PC
Workgroup : WORKGROUP

Computer
Model : GigaByte P55A-UD3R
Chassis : GigaByte Desktop
Mainboard : GigaByte P55A-UD3R
BIOS : Award (OEM) F9 05/03/2010
Total Memory : 8GB DIMM DDR3

Processors
Processor : Intel(R) Core(TM) i7 CPU 870 @ 2.93GHz (4C 8T 3GHz/3.59GHz, 2.4GHz IMC, 4x 256kB L2, 8MB L3)
Socket/Slot : FC LGA1156

Chipset
Memory Controller : Gigabyte Core (Clarksfield/Lynnfield) DMI 2x 2.4GHz (4.79GHz)
Memory Controller : Gigabyte Core Desktop (Lynnfield) UnCore 2x 2.4GHz (4.79GHz), 2x 4GB DIMM DDR3 1.33GHz 128-bit

Memory Module(s)
Memory Module : G.Skill F3-12800CL9-4GBRL 4GB DIMM DDR3 PC3-12800U DDR3-1600 (9-9-9-25 4-34-10-5)

Video System
Monitor/Panel : LG W2353
(1920x1080, 23.1")
Monitor/Panel : Samsung SAMSUNG
(1680x1050, 19.0")
Video Adapter : NVIDIA GeForce GTX 460 (7CU 336SP SM5.0 1.43GHz, 1GB 3.61GHz, PCIe 2.00 x16)
Video Adapter : NVIDIA GeForce GTX 460 (7CU 336SP SM5.0 1.43GHz, 1GB 3.61GHz, PCIe 2.00 x16)

Graphics Processor
OpenCL GP Processor : NVIDIA GeForce GTX 460 (336SP 7C 1.43GHz, 1GB 3.61GHz)
Compute Shader Processor : NVIDIA GeForce GTX 460 (336SP 7C 1.43GHz, 1GB 3.61GHz)

Storage Devices
WDC WD1002FAEX-00Z3A0 (1TB, SATA600, 3.5", 7200rpm) : 932GB (E:)
WDC WD15EARS-00Z5B1 (1.5TB, SATA300, 3.5") : 1TB (G:)
Samsung SSD 840 Series (120GB, SATA600, SSD) : 112GB (C:)
SanDisk Cruzer Edge (8GB, USB2) : 7GB (H:)
SAMSUNG DVDWBD SH-B083L (713MB, SATA150, BD-R, DVD+-RW, CD-RW, 2MB Cache) : 680MB (D:)
ELBY CLONEDRIVE (SCSI, SCSI-2, BD-R, HD-DVD-R, DVD-R, CD-R, 256kB Cache) : N/A (F:)

Logical Storage Devices
Dan Audio (E:) : 932GB (NTFS) @ WDC WD1002FAEX-00Z3A0 (1TB, SATA600, 3.5", 7200rpm)
System Reserved : 100MB (NTFS)
Removable Drive (H:) : 7GB (FAT32) @ SanDisk Cruzer Edge (8GB, USB2)
OS Disk (C:) : 112GB (NTFS) @ Samsung SSD 840 Series (120GB, SATA600, SSD)
System Reserved : 100MB (NTFS)
Storage (G:) : 1TB (NTFS) @ WDC WD15EARS-00Z5B1 (1.5TB, SATA300, 3.5")
GV-N460_10 (D:) : 680MB (CDFS) @ SAMSUNG DVDWBD SH-B083L (713MB, SATA150, BD-R, DVD+-RW, CD-RW, 2MB Cache)
Optical Drive (F:) : N/A @ ELBY CLONEDRIVE (SCSI, SCSI-2, BD-R, HD-DVD-R, DVD-R, CD-R, 256kB Cache)

Peripherals
LPC Hub Controller 1 : Gigabyte P55 LPC Interface Controller
LPC Legacy Controller 1 : ITE IT8720F
Audio Device : Gigabyte P55/PM55/3400 High Definition Audio
Audio Device : Gigabyte GF104 High Definition Audio Controller
Audio Codec : nVidia 0012
Audio Codec : nVidia 0012
Audio Codec : nVidia 0012
Serial Port(s) : 1
Parallel Port(s) : 1
Disk Controller : Gigabyte ICH8R (ICH8) SATA RAID Controller
Disk Controller : Gigabyte 88SE91A3 SATA-600 Controller
Disk Controller : Gigabyte JMB36X PCIE-to-SATAII/IDE RAID Controller
Disk Controller : Gigabyte IT8213 IDE Controller
USB Controller 1 : Gigabyte P55/PM55/3400 USB2 Enhanced Host Controller
USB Controller 2 : Gigabyte P55/PM55/3400 USB2 Enhanced Host Controller
USB Controller 3 : Gigabyte Renesas Electronics USB 3.0 Host Controller
SMBus/i2c Controller 1 : Intel ICH SMBus

Printers and Faxes
Printer : Send To Microsoft OneNote 2010 Driver (1200x1200, Colour)
Printer : Microsoft XPS Document Writer (600x600, Colour)
Fax : Microsoft Shared Fax Driver (200x200)

Peripherals
Media Player : SanDisk Cruzer Edge (7.42GB)

Network Services
Network Adapter : Realtek PCIe GBE Family Controller (Ethernet, 1Gbps)

Operating System
Windows System : Microsoft Windows 7 Home 6.01.7601 (Service Pack 1)
Platform Compliance : x64

Windows Experience Index
Current System : 7.3

[dbooth]

To answer your questions...

- The noise is present regardless of any particular plugins being used and is slightly worse on PT load up when the HDD is working harder
- I have tested at three different residences so far and the results were the same
- I just switched out the 3rd Gen M-box for my old 2nd gen and there was no difference
- I tried several different drivers for the m-box and there were no changes
- I will have to wait to get a powered hub, but I unplugged my m-box, and the casing noise was still present
- I am not sure appliances such as electric motors or fridges are not in the circuit, however unplugging all these items does nothing to change the noise

Thanks Dan

[dave911]

The sound coming from the case sounds like the switching power supply is whining.
The fact that the frequency changes as you change loads also suggests the power supply. Could be the output filter is letting switching noise onto the PC supply bus.
Also have you add a battery backup recently, some of them can introduce switching noise.

[dbooth]

Originally Posted by dave911

The sound coming from the case sounds like the switching power supply is whining.
The fact that the frequency changes as you change loads also suggests the power supply. Could be the output filter is letting switching noise onto the PC supply bus.
Also have you add a battery backup recently, some of them can introduce switching noise.

No, I only recently moved the operating system over to the SSD as my C drive, but the problem existed before then anyway.

Power supplies are reasonably cheap, but how do you know for sure if replacing it would fix the problem?

Also not very clued up about the pc hardware side of things. Is there a definitive way to test it?

[mjslakeridge]

You can get some free software to monitor the voltages produced by the power supply, but that alone might not detect a problem with the output filter as Dave911 described. In your original post you said the noise was present even when you used the Mbox and speakers with a different computer (laptop), plugged into the wall socket, but when on battery power the noise went away. That is why I was asking about sources of interference on your A/C power circuit.
Is the noise present only when using pro tools? or can you replicate the problem when using any other program with the speakers connected?

[dbooth]

Originally Posted by mjslakeridge

You can get some free software to monitor the voltages produced by the power supply, but that alone might not detect a problem with the output filter as Dave911 described. In your original post you said the noise was present even when you used the Mbox and speakers with a different computer (laptop), plugged into the wall socket, but when on battery power the noise went away. That is why I was asking about sources of interference on your A/C power circuit.
Is the noise present only when using pro tools? or can you replicate the problem when using any other program with the speakers connected?

Yeah, it's not just Pro Tools that causes it, just simply turning on the speaker while connected to the M-Box via usb is enough - with the desktop unit that is. Of course it makes morse code like sounds on load up of PT and throughout operation when it is switching between cpu loads - simular to the 1kHz sound I described.

By way of interest, the power supply was upgraded when I bought the PC, from the original casing. It was originally a 450W Thermaltake Model:TT-450NL1NH-1, which I still have unused in a box, and upgraded to a Corsair TX650W Power Supply Model: CMPSU-650TX. Dunno if that helps?