T520 Audio Crackling

[Nigel-S]

Had the laptop for about a month now. Ran all necessary updates and still having a problem with audio playback constantly 'crackling'. Any sort of audio playback will do it, just annoying crackles in the background which make listening to anything impossible.

Enormous red spikes constantly on the DCP latency checker.

Windows 7 64bit

[ColonelONeill]

Try LatencyMon instead; it will list the precise drivers that are causing the issue.

Also try uninstalling the Intel Management stuff if you don't need it. The AMT driver adds a bit to latencies in my experience.

[enovola]

Work office just bought 12 t520's. Thought it was just my own device having the crackling sound. Went back to work and tried multiple machines and sure enough it's happening on all of them. This problem is on top of the already dismal max volume which barely fills a room.

[paxtonbt]

I would keep this thread open for awhile. Most latency problems are solved with a BIOS update, I think. Lenovo gave us one to solve latency spikes on the ThinkStation S20.

[NINE]

hi all,

Was reading through this thread and wanted to check was there anything in particular that you had installed Prior to it happening? Its really hard to pin point what the cause as many factors come to my mind. Harware could be one of them but before i conclude it is hard ware would like to eliminate the possibilities of software first. 

In the past there were something similar to this issues where by uninstalling the Mcafee Antivirus Did the trick. I woulod suggest trying to uninstall the Mcafee First and check for the changes (Only applies to thise that have Mcafee Preinstalled on the machine).

Do let me know of the changes.

Regards

[NINE]

hi all,

Just wanted to check with you if you had tried my suggestion earlier? Do let me know of the changes.

Regards

[Nigel-S]

Thanks for keeping this open. I don`t believe this started after any installs, but I don`t exactly recall when I started noticing it.

I've ran latency checker for a bit, which pointed to iaStor.sys (Intel Rapid Storage Driver). I tried installing different releases of these drivers, or finding an alternative but no luck.

I called Lenovo support and a technician remoted into my PC and checked that all drivers were up to date, but there was still no solution.

I found a thread which mentioned disabling the nVidia NVS 4200M, so I did this and the latency problem stopped. This of course is a temporary fix, and I would like to get to the bottom of it (however, it`s worth mentioning to anyone with this issue).

I use Symantec Endpoint Protection, as well as MBAM, but I don`t think they`re the culprit.

[tripplec]

Is the Nvidia active GPU when this is happening? There is an Nvidia sound driver part of the Nvidia Optimus package. But if control panel show you're running the Intel GPU it should not be related. Just a though. I have now problem here but I an not using the Lenovo drivers since the caused many problems when I got the system I went to another driver set from Nvidia

[Nigel-S]

No, NVIDIA GPU isn't running at the time. The NVIDIA only kicks in during high intense graphics (games mostly). 

Here are some screenshots of LatencyMon with and without the NVIDIA driver enabled.

http://i.imgur.com/p9HWd.png (Enabled)

http://i.imgur.com/AXaWx.png (Disabled)

[tripplec]

I went back and don't see  the spec's on your machine!

No CPU, memory etc which is a basis for analysis.

Clearly you have the right audio drivers and if it doing it with music playback from say Itunes or a music CD. I would have to say it must be a hardware problem in which you'd have to take it in for service.