Music Stutters

[Scroobius]

Hi Peter
I have xx09y4 running with engine#3. The problem is that the music "stutters" (ie music plays for 1 sec stops for 1 sec runs for 1 sec and so on) for first 30 secs of a track then settles down and plays continuously. If it is a long track sometimes it stutters for a few seconds in the middle a track. I have checked processes in task manager and I cannot see any other process cutting in (I wondered if another process might me interfering). Checking "relaibility & performance" with xx running seems OK with cpu 39% peaking 83% disk 0% peaking 3% memory 73% (53% xx not running) regardless of whether stuttering or not.

System is HP Pavillion dv9500 laptop, Intel Core Duo, Vista Home Premium SP2, memory 2gig.  Off Ramp to Audio Note DAC2.1.

I am running 2 x upsampling with Arc Prediction (xx running in administrator mode) although the above problems occur regardless whether upsampling or not.

Attached is copy of the settings page.

I hope you can help because the sound quality is amazing (even with Pace Car removed which will only pass 24 96)

Question : I do not understand upsampling. I thought that with a 24/44.1 native file 2x upsampling would change that to 24/88.2 but I must be wrong because off ramp will only pass 24/44.1 24/48 & 24/96 and it works.

Hope you can help I cannot live with 09y4 sound quality now I have heard it.
All the best
Paul

[PeterSt]

Hi Paul,

Question : I do not understand upsampling. I thought that with a 24/44.1 native file 2x upsampling would change that to 24/88.2 but I must be wrong because off ramp will only pass 24/44.1 24/48 & 24/96 and it works.

Nope. The OffRamp also does 24/88.2. That's why.
You can't see this in Vista, because it only shows (and allows) the rates to resample to, and 88.2 is not amongst it (as 176.4 is not). So to keep in mind : what Vista shows is not the output capabilities of the DAC (told by the driver) but Vista's own reample-to capabilities.


On to the real thing;

Try to set the Player Priority to Low and the Thread Priority to RealTime. Furthermore set the Core Appointment Scheme to 3.
Next tick Stop Services (and Running Time OSD plus OSD Text if you want).
Tick Start Engine3 during conversion to tease things (this makes it worse again !).
Tick Unattended in the main screen (at the bottom).

Click Play and run away.
If all is right this helps and you can go back into the room within that 30 seconds, not being sure whether they have passed already. But, sound will be better again !

If this doesn't help, untick that Start Engine3 during conversion, and try again.

But if it doesn't help, I can't imagine that it is still exactly the same, so please describe the difference in that case.

with xx running seems OK with cpu 39% peaking 83% disk 0% peaking 3% memory 73% (53% xx not running)

Something doesn't seem even here. A number too many or a word too few, I can't tell. But anyway, when you just clicked play at ATtended (!) and sound plays, XXHighEnd as well as XXEngine3 should show 0 %. Notice that this doesn't count for throughout the track, which is caused by your "Split ile at size" setting (which is no problem at all, but it implies you're only allowed to look at the cpu right after playback has started, not much later (like some 40-45 seconds with this setting and Doubling)).

Let me know what happens !
Peter

[Scroobius]

Hi Peter
I have tried the settings you recomended but unfortunately the music still stutters. I then switched off "Start engine#3 during conversion" but still I have the same stuttering problem.

I dont want to use engine#2 but if I try and run engine#2 I get a "not enough system resources memory?" message. Not a problem as I only want to use engine#3 but thought I would mention it if it helps to diagnose the problem.

I dont have any problems running 09x7 with engine#2.

Any ideas would be welcome.

Is my laptop spec up to the job?

All the best
Paul

[PeterSt]

Hi Paul,

This is certainly not what I expected; ortherwise I wouldn't have been joking about it. Hmm ...

Is your laptop on spec ? well, laptops never really are IMO, but this case seems not to be in that "leage".

Allright, problems are there to solve;
Somehow I have the feeling that your laptop is doing something strange with its memory. Now, for now just keep those settings I advised, and do as follows :

Switch off the virtual memory (swap file) for your OS disk (you probably have one disk in there anyway). This means that when more memory is needed than you actually have, you will receive out of memory errors (don't use Engine#2, which is a different beast and/or problem. So only use Engine#3). With your 100MB Split file setting you should be able to have all in memory easily, and you should not receive an out of memory error. But I suspect you will receive it anyway ...

I base this on a one explanation I can think of about these 30 seconds stuttering, and this is about reorganizing that virtual memory. This has the highest priority of all and just *will* interrupt sound when in order (too heavily). But then the point is, you shouldn't be using it, although it is always used by Vista because it "preloads" stuff in there, without it being necessary. This means that when you run out of memory, Vista has been smart and that that time the memory doesn't need to swap out to the disk because it already has been done. This can just be avoided by shutting it off. Of course this only works when you're not in lack of memory, but again, with these settings "officially" you won't. Or not for this playback anyway. Of course I am not talking about the other things you may do with the laptop, so this is only a test.

When you look at TaskManager, you still may see "virtual memory" in use, no matter it has been shut off. This is because withing the normal physical memory there's *also* virtual memory, and it is exactly there where your "available" memory may be eaten. It differs per processor or OS implementation, and maybe nobody understands how or why. In my case I have 1.3GB available from the 2GB, and only in special cases I can consume the full 2GB. It is my suggestion that in your case you have even less available, and therefore the swapfile comes into play, and *that* bugs your sound, plus it is a typicle thing which may last a longer time (like 30 seconds).

If you don't understand this all, don't try to. Switching off that virtual memory is sufficient to prove I am right (or not).
If you don't receive out of memory errors, of course try whether the problem is solved.
Depending on the results we will proceed from there.

Peter


PS: Start Explorer, rightclick on Computer - choose Properties, click Advanced System Settings, click Settings under Performance, click Advanced tab, click Change under Virtual Memory, tick No paging file, click Set

[Scroobius]

Peter - I switched off page filing and it does not appear to have affected the sound - the stuttering still happens.

Regards

Paul

[PeterSt]

I am speechless.

With the page file off (remember, just for now, and just for (further) testing), do you perhaps see heavy disk I/O (the disk light) during the stutter period ?

Also, do you have any wireless stuff active (including infrared keyboard or mouse) ?

[Scroobius]

Peter - disk activity not affected and wireless switched off still the same problem.

But that set me thinking that if it is not directly xx then it could somehow be control of the data out of usb. Well I have a very very long USB cable to my off ramp with an active hub in the middle. This set up has always worked no problem before with other media players (foobar, windows media player) and 09x versions of xx. So I took my laptop away from my comfy chair to the off ramp and plugged in a short usb cable direct into the off ramp. SUCCESS it works no problem now and the sound WOW is just superb.

I would be interested in your thoughts as to why it might be a problem. Actually it is probably nothing to with 09y as such could it be to do with the fact that I am using engine#3 for the first time ? (#3 did not work with off ramp in 09x7 of course) and enigne#3 uses exclusive mode in Vista right ?. Just a thought.

Now the problem is that I cannot use Pace Car except with native 24/96 files and boy oh boy does it sound good with those. The problem is that the sound improvement is so great with 09y4 & engine#3 that it swamps the sound improvement of Pace Car (which in turn makes a big difference). Also I have to get out of my comfy chair to change albums (never mind!!).

Keep up the good work Peter I am stunned with the sound improvement and now I can bypass my expensive Audio Note pre amp (highly modified at great expense kit !!!!). I will try that tonight - can't wait (like a little boy with a new toy).

Thanks for your support fantastic really appreciated.

All the best
Paul

[PeterSt]

Aha !! but now why ...

Try to imagine that as soon as you hear sound (and checking this at ATtended is the most safe) the file (part) *must* have been transferred to the PC's memory in full, or otherwise there's no way sound will (have) start(ed). This also means, that as soon as you hear sound, there's not a single bit additionally transferred. Btw, this is confirmed by your disk activity (not showing anything anymore).

Side note : that this works differently with Foobar etc. or for Engine#2 for that matter, is because of the additional processing Engine3 is doing. This won't be the case with Foobar, and sure is not the case with Engine2 (or 1). The other things should be the same (data transfer), like Engine2 will just read the complete file into memory, and Foobar will when the buffer for it is set large enough.

So it must be the processing that kills, BUT :

Exactly the same as I talked about above, when sound starts, *all* processing has been done just teh same. Now what ?

As I suggested earlier, this is an unknown problem (at least to me it is).
The only thing I can think of right now is somehow the USB bus is stressed, even after all data has been transferred to the PC's memory. Btw, it is clear to me that your connection is longer than what it can actually take for normal operation, which is something you may have never noticed (resends went unnoticed). Now I wonder, you are not using USB disks, are you ? Not that it would justify the problem in this case (without further thinking), but at least it is so that using the USB bus for normal data while using an USB connected DAC is *never* a good thing to do. This by itself (for XXHE) would only be noticeable at track(part) loads, and music easily stalling.

Very far away it can be so that at the first burst of music data towards the DAC - which really would be the largest burst during playback of all - the resends with the too long connection are too many, and that by itself consuming (high priority) CPU. Now a kind of chain reaction occurs, and the CPU working at the resending is not able to continuesly stream the data (to the same USB bus, but the process is a different one).

Something like that ?

Well, the most good you tried this ! and the most nice to hear you so enhusiast !
Peter


PS: You may try the long connection without the active hub, since the OffRamp is powered. It may feed the USB bus with its own power. If so, you can use some 10 meters. All I'm saying is : although an active hub may extend the useable length of USB, it is not said this works well for the streaming audio part. On that matter my own Firewire connection of 10 meters does not work with an active hub for streaming audio (controlling the device for settings, no problem), while just using plain 10 meters of Firewire cable does work. But, the device behind it doesn't need the power from the Firewire cable. Same with an USB DAC I have ... it just works with over 10 meters of USB (with extension cables, because 10 meters USB in one piece does not exist AFAIK).

[Scroobius]

have moved to new topic

[Scroobius]

Hey Peter
That seems to have sorted it will test on a llonger listening session tonight and then will try connecting direct to the power amps - taking the pre amp out of circuit will be interesting.

All I have to do now is see if I can get an 88.2k clock fitted to my Pace Car

Thanks
Paul

[PeterSt]

Hi Paul,

I am not sure whether you posted this last post in the right topic ?
I mean, is your disc jogg problem solved perhaps ?

Thanks,
Peter

[Scroobius]

Peter - the disc jog problem was sorted with changing the q setting to 14 so on to some proper listening. Have had a couple of minor glitches but basically seems to be OK subject to more extended listening
Thanks for your help
Paul