[kretara]

I've noticed something new (in the last month) on my DP 2.0 G5.

I have a 24GB iTunes folder and I have iTunes playing for about 8 hours a day at work.
After a period of time (sometimes a few hours, sometimes a few days) the music (either via the rear speaker jack going to my JBL Creatures) or via the internal speaker gets really choppy and distorted. The only way to "fix" this is to close iTunes and restart it.
If I pause iTunes and play music from a different source (internet radio not through iTunes) I do not hear the distortion.

I do run Folding on this machine. Not sure if that would have much to anything to do with this.

Has anyone experienced anything like this? Anybody have any suggestions?

[kretara]

Knock, Knock!
Hello, is anybody there......

[zman2005]

Oh, I am here baby. I just have no idea

[Ebby]

I never heard of something like this before. My only suggestion is to turn off the equalizer and/or Sound enhancer. Perhaps they are messing up somehow.

[kretara]

good idea!
I'll try that and see if it helps.

[kretara]

Nope, didn't fix the problem.

I've been listening to iTunes (music from my HD) for the past 1.5 hours (I restarted iTunes 1 hour ago) and the distortion is coming back. As long as I am not doing anything the music is clear.
But, if I drag lets say a BBEdit window across my 3 screens the music playback gets real choppy. Opening apps also make the music choppy.
This is all with folding stopped but I am transferring 30GB of data from my G5 (affected machine) to my PB right now. This should not matter though. According to top I am ~78% idle.

[Hawk]

Do you have any PCI cards installed in your system? I had a huge problem with my Radeon 7000. I was told to buy a new card to fix the problem. Anytime there was motion on a display connected to the 7000, audio would start to break up. I ended up just taking out the card...

[kretara]

Yeah, I have a Radeon 9200 (PCI) installed. Now that you mention the pci card I remember that the distorotion was "worse" on the screen with my PCI card.

Looks like I'll contact Apple when I get back from vacation.

Thanks!!!!

i have a simlar problem, but ALL 7300+ songs of mine get distorted after about 1:30 to 2:00 minutes into the song. they all play perfect in Winamp, but any help would be great

[Ocelot]

I had a problem with iTunes skipping when I performed simple GUI interactions with other apps (but not with iTunes). CPU usage was spiking but not at 100%, as measured by activity monitor. I tried everything, even going so far as to create a new user account that ran as few processes as possible, but iTunes kept skipping. Move an item in the finder and it skipped, open a new browser window and it skipped, etc.

When I updated to Panther, the problem vanished. But for about 3 months I had to put up with the skipping and could not find the source.

I have no idea how this relates to your problem, other than being another iTunes oddity. Maybe Apple puts these bugs in the later point releases of each major release, so Mac users have more incentive to upgrade to the next release! /tinfoil

[kretara]

Just a little update.
I had a general bitch session with Apple about this issue.
They sent someone out to replace the power supply in my G5 and to test some stuff out.

The replaced power supply did nothing and their tech was left scratching his head.

Their best guess was that there was too much traffic coming over the PCI bus, which was causing distortion in audio whenever ANYTHING was done on my third screen (driven by a PCI Radeon 9200). Basically, they said that I would have to live with it. I'm not at all happy with this answer since an old B&W that I had could push 3 screens (via 2 PCI video cards) and not distort music playback and same with 3 different G4 PM's that I owned.

[Dave]

AHAHAHAHAHA!!!!!
Too much traffic on the PCI bus?!?

What a load of crap! They're just saying that because they can't figure out what's making it do that.

[DMBand0026]

Really dude. If I were you I'd raise some serious hell about that. That's a grade A copout right there if I ever heard one.

[Gargoyle]

Originally Posted by kretara This is all with folding stopped but I am transferring 30GB of data from my G5 (affected machine) to my PB right now. This should not matter though. According to top I am ~78% idle.

That's because the transfer (was it by firewire, ethernet, wi-fi?) will probably be using DMA to access the drive without needing to ask the CPU to do it. In other words, copying a large amount of data from the HD is not necessarily a CPU intensive task.

However, your machine should be able to handle it. I am currently listening to a fairly mellow song, which should let me hear any distortion or pause even if it was really small, while repairing the permissions on my drive - and this is a powerbook drive!

A few other bit of information you could divulge are the type of file you are playing? Are they mp3's, streaming radio, aac, wav? Also, compare the mem and cpu usage of iTunes when you first launch it, to when it starts to break up. With the GUI open and playing 128Kbps AAC - iTunes uses about 8% CPU on my PowerBook, if I close the window the CPU usage is more like a 3% average.

Finally, if can bare to live with just the 2 screens for a day you could remove the "alleged" offending PCI card to verify if it is somehow causing the decay in iTunes performance.

[kretara]

The addition of the PCI video card is 'causing' the problem. I've tried a Radeon 9200 and an old Radeon 7000 (in each PCI slot), no matter what there was still distortion in audio playback.
The audio distortion happens with both the rear and front jacks, and it occurs worse with iTunes but I have also heard it with quicktime movies.

iTunes CPU usage is between 5-8%. There is no CPU change or memory change when distortion occurs, although the longer I play iTunes the more frequent the distortion.
I am playing a mix of AAC (m4a) and mp3 files and it occurs with both file types.

I guess one of the issues is that this issue is not always repeatable. One minute it will distort like crazy just by clicking on an open windown in the third screen and 1 minute later (same song) no distortion will occur no matter what I do. Its crazy.

Regardless, I've talked to our Higher Ed. Sales Rep. and I told her that
1. due to quality control issues with powerbooks (our 12" PB's have had more issues than our Dell laptops; and the lower slot RAM issue with the 15" PB) that we were not going to buy any PB's until Apple gets their shit together.

2. We (our department) are considering making the switch from Dell's to Apples once Apple goes to Intel. I told her that if they can't take care of such a small issue as my PM sound problem then we can't have confidence in Apple service for the long term. Which means we will stick with Dell.

3. There are other Mac users on campus who are aware of my issues and are waiting to hear Apples response.

I've got some leverage, but Apple just does not seem to care (at least not like they used to) about quality and we (the University) get brushed off a bit by their sales reps. Looks like Apple is abandoning the higher ed market for the trendy iPod people.