Process priority - iTunes and that "bzzzt"
 

Hi guys - I'm rather enjoying occasionally reverting to the 80s using internet radio on iTunes. Sad eh? :)

Anyway, whenever I resume the desktop, iTunes (9.2) gives a short "bzzzt". So it seems to me the PC isn't giving iTunes the resources it needs at times. This "bzzzt" can also occur (rarely) when the PC is busy.

It's an older Dell, dual core 3.4 GHz with 4Gb RAM, Win 7 Professional 32 bit. I kinda think this should be plenty for iTunes, and it's rare for other resource hogs to be running.

My first thought was to assign a higher priority, however it seems that doing so in the task manager only remains current for the session. The world wide wait according to Google is suitably vague (more likely user issues AKA GIGO).

Does anyone have experience with Prio - Priority Saver, or can you recommend some other ways to give iTunes full priority - perhaps give it 100% of one of the cores?

Pretty sure the problem isn't your machine. It should be able to easily handle internet radio and iTunes.

I'd first check what other processes are running and their CPU use. If all's in order, it's probably just a problem with the radio feed. Do you have the problem with all internet radio or just this one? How about when playing mp3's locally?

You can set process priority in the task manager by right clicking a process.

1) I've had problems with Vista and audio - they seemed to go away with Win 7, but I haven't tried some of the same software since switching. You might try some things which helped with Vista:
(A) making sure you've got the best audio driver for your hardware (this might be the newest from Dell, the newest from the chipset manufacturer, or the default one from Microsoft. Google is your friend here; IME if there is a Microsoft-provided driver, it's usually best, but in many cases they don't have an out-of-the-box sound driver for all the realtec and sigmatel chips Dell tends to use.
(B) try turning audio "enhancements" off (control panels->sounds->playback devices->speakers->Enhancements tab) - this can reduce issues with CPU utilization
(C) try turning exclusive mode off (same as above, but "advanced" tab)

2) You can give an application top priority use of one core manually via task manager - right click on the task bar, select "start task manager", when it comes up click "show processes from all users" (you may get a UAC prompt, if so select yes), then right click the process (presumably itunes) and select set affinity and then uncheck all but one processor. Then click OK, and right click the same process, and set priority to high or realtime.

Thank for the tips. I had another serious crack at it last night. A process called "system interrupts" keeps briefly appearing at the top of the CPU usage in the resource monitor. Hmm.


Downloaded and ran the DPC Latency Checker.

Red bars everywhere.

Updated all audio, USB, LAN and video drivers - a nice feature of Win 7. Disconnected 2 USB hubs (one of which is the Dell screen), disabled the 4 card readers on the front panel. Also moved the page file to the 2nd HDD and fixed it at 5373 Mb (recommended by Win 7).

Far fewer red bars, the "system interrupts" is rarely showing as a CPU hog, however the "bzzzt" and audio drop outs still keep happening, at a reduced frequency. Re-enabled devices one by one, and no real change to the system state.

I'm now almost certain the problem is the MS wireless keyboard and mouse. Will try a wired version of both tonight...and if that doesn't work it would appear (sigh) a fresh Win 7 format and installation required...

The problem was the MS Wireless keyboard and mouse. Gone from 16,000+ µs when using the keyboard or the mouse to a maximum of 854 µs, which occurred when I opened Thunderbird - which is a bit resource hungry - while streaming iTunes.

Bugger...