Gutted I am.... Latency. Ready to SMASH my laptop

Noel · Post by **Noel** » Mon Sep 15, 2008 6:41 pm

A company called "Centrance" provides this neat asio latency test utility

http://www.centrance.com/downloads/ltu/

It measures the total round trip time from input to output. It won't fix your problem but it will let you measure your latency independent of Live.

gjm · Post by **gjm** » Tue Sep 16, 2008 9:02 am

rozling wrote: And how are you checking your latency - when you say you can't get it below 1024/55ms, do you get clicks and pops below that or just nothing?

I just want to make sure I am on the right page.

I am checking my latency using the test tone in the Audio Preferences Dialogue box as suggested by the lesson on setting up Audio I/O.

At 768 samples its all cracked and fuzzy.
At 1024 samples the tone is clear.

Have I got this right? I don't know what the implication of the Ableton test is, and if it is the correct bench mark for me to be fussing about.

Alternatively, I can go down to 192 samples @12.2ms just recording 1 guitar track. At this point the sound is clear with occasional but significant dropouts. At 128 samples its 'all over rover' totally broken up.

There is definitely something happening in the background as indicated by the DPC Latency System test that leedsquietman referred to. Turning off the wireless networking card made a big difference. I am not really sure what else to turn off using device manager.

My hard drive was new 3 months ago, with only 5% used space.

I also loaded a fresh vanilla install of XP.

I still have not got to most of the suggestions yet. I will get to them over the next few weeks.

One idea I had was to grab back some of the ram from the video card. Apparently on the R3000 you can set up the amount of video ram through the system bios???? I don't know how easy this is but I think its currently set to 128mb, and I could drop it to 64 or even 32. I don't know if that will aid in making the system work better.

Computers challenge me, to say the least. I am also just dog tired as well. Makes it easy to dream about running the laptop through a table saw. I know my lappy is kinda old and all that, but I just don't have the freight to upgrade right now. So I will, as Tone Deft pointed out, 'pay my dues.'

nolus · Post by **nolus** » Tue Sep 16, 2008 10:40 am

disabling wireless / bluetooth, power/battery management and the builtin soundcard, modem and webcam makes the biggest improvement on my PC.

leedsquietman · Post by **leedsquietman** » Wed Sep 17, 2008 2:36 am

If the DPC latency test is showing high activity without much going on, you may have ar IRQ conflict or something going on.

Look at your IRQs and see if something is sharing the same IRQ as the firewire chipset and if so try moving the IRQ to a free channel or something which isn't being used often (you'd be surprised how many times the USB chipset is set to the same IRQ as firewwire and if you are accessing both at the same time, a bottleneck is going to occur).

Which firewire chipset (IEE1394) are you using? Check this in control panel system device manager etc. It might be that your chipset is not working, or is a cheapie which requires extra workarounds or even replacement with a PCI>IEE1394 adapter that featires a Texas Instruments firewire chipset (TI chipsets have historically been the most stable and best performing). Do you gave another FW cable you can check in case you have a faulty cable. Also check for electrical ground loops and stuff like that.

adventurepants_ · Post by **adventurepants_** » Wed Sep 17, 2008 2:44 am

i had a funny problem with my Firebox and Live. I was getting an IRQ conflict between my video card (8800gt) and the firewire controller. After trying a few fixes, just turning graphics acceleration down to the minimum fixed all the problems.

Before this, DPC reported red spikes every time i moved a control in Live. This was after getting a TI chipset PCI express card.

Firewire is pretty poorly implemented on Windows i gotta say.

gjm · Post by **gjm** » Wed Sep 17, 2008 4:51 am

leedsquietman wrote:If the DPC latency test is showing high activity without much going on, you may have ar IRQ conflict or something going on.

When I turn off the wireless 802.11b in the Network Adapters, most of the red spikes disappear. I am left mainly with yellow spikes that do not trigger the 'bad news' message. If I walk away for 10 mins or so then something has triggered a red spike and the bad news message. I think the idea is to get the activity all green, eh?

Look at your IRQs and see if something is sharing the same IRQ as the firewire chipset and if so try moving the IRQ to a free channel or something which isn't being used often (you'd be surprised how many times the USB chipset is set to the same IRQ as firewwire and if you are accessing both at the same time, a bottleneck is going to occur).

I have a friend who might be able to help here. Probably 2 days away yet.

Which firewire chipset (IEE1394) are you using?

Texas Instruments OHCI Complient IEEE 1934 Host Controller. Is that it?

Do you gave another FW cable you can check in case you have a faulty cable.

I'll have to pick one up.

Also check for electrical ground loops and stuff like that.

I'll hit my neighbor up, he's an electrician.

Thanks.

gjm · Post by **gjm** » Thu Sep 18, 2008 10:06 am

leedsquietman wrote:Look at your IRQs and see if something is sharing the same IRQ as the firewire chipset and if so try moving the IRQ to a free channel or something which isn't being used often (you'd be surprised how many times the USB chipset is set to the same IRQ as firewwire and if you are accessing both at the same time, a bottleneck is going to occur).

Firewire Controller = IRQ 16
PCI to USB Host Controller = IRQ 16

Now the question is, can some one tell me how to change this? Is it fairly simple, or am I better off taking my lappy to a tech shop?

adventurepants_ · Post by **adventurepants_** » Thu Sep 18, 2008 10:33 am

gjm wrote:
leedsquietman wrote:Look at your IRQs and see if something is sharing the same IRQ as the firewire chipset and if so try moving the IRQ to a free channel or something which isn't being used often (you'd be surprised how many times the USB chipset is set to the same IRQ as firewwire and if you are accessing both at the same time, a bottleneck is going to occur).
Firewire Controller = IRQ 16
PCI to USB Host Controller = IRQ 16

Now the question is, can some one tell me how to change this? Is it fairly simple, or am I better off taking my lappy to a tech shop?

just for laughs, turn your graphics acceleration slider all the way down and reboot, and see if it improves performance any further.

control panel -display - settings - advanced - troubleshoot

ekwipt · Post by **ekwipt** » Thu Sep 18, 2008 11:31 am

Set Processor Scheduling for Background Services

Normally, Windows XP is set to give higher priority to the program that you are currently working in (the one which is focused). This would seem to make sense for DAW use, but for maximum performance set this to Background services. This allows effects, synthesizers, and everything else besides the main SONAR thread to have an equal chance at grabbing the CPU and will provide more even DAW performance.

You can give background processes priority by going to Settings | Control Panel | System, and then choosing the Advanced tab and clicking on the "Settings" button in Performance. Then click on Settings, select the Advanced tab, and select Processor Scheduling to "Background services". You will probably need to reboot to make this change take effect.

gjm · Post by **gjm** » Fri Sep 19, 2008 5:31 am

List of things done to date.

1. Set processor scheduling to background services.
2. Reduced the Graphics Acceleration slider to None.
3. In Device manager I have disabled
- Compliant Control Method Battery
- Floppy Disk Controller
- Modem
- Wireless 802.11b Network Adapter
- Ethernet Network Adapter
4. Set Visual Effects to minimum
5. Switch off Desktop Background Image
6. Disable Screen Saver
7. Switch off Power Schemes
8. Adjusted the Swap File Virtual Memory to 1.5x Ram for initial and maximum.
9. Have double check the FireWire driver and have run a SP1 version as well as SP3 driver. There are no further updates to be had.
10. Have defraged. (New 250GB HD 3 months ago) Tonnes of room left.

The DPC Latency tool still occasionally gives me the "bad news" message.
More importantly my latency has no changed.
Using the Ableton test tone system I still have 1024 samples @ 50m/s for clean clear sound. Anything lower starts to break up.

I guess I am stuffed.

adventurepants_ · Post by **adventurepants_** » Fri Sep 19, 2008 5:40 am

man that sucks.

have you tried another DAW? download Reaper, and throw a few tracks in it and see how it goes. Halfway through tracking down my firewire issues, i discovered that Live was giving me bigger spikes than anything else.

gjm · Post by **gjm** » Fri Sep 19, 2008 6:01 am

adventurepants_ wrote:man that sucks.

have you tried another DAW? download Reaper, and throw a few tracks in it and see how it goes. Halfway through tracking down my firewire issues, i discovered that Live was giving me bigger spikes than anything else.

So are you saying that its not necessarily all my computers fault for the high latency? Another DAW might produce a better latency result?

rozling · Post by **rozling** » Fri Sep 19, 2008 7:33 am

gjm wrote:
leedsquietman wrote:Look at your IRQs and see if something is sharing the same IRQ as the firewire chipset and if so try moving the IRQ to a free channel or something which isn't being used often (you'd be surprised how many times the USB chipset is set to the same IRQ as firewwire and if you are accessing both at the same time, a bottleneck is going to occur).
Firewire Controller = IRQ 16
PCI to USB Host Controller = IRQ 16

Now the question is, can some one tell me how to change this? Is it fairly simple, or am I better off taking my lappy to a tech shop?

I'm pretty sure this is worth checking out before you give up - tbh I thought this was a good candidate for being the source of the prob. I'm not sure exactly how you go about changing the IRQ/moving to a dedicated IRQ but a quick Google should tell you... maybe put in the term 'audio' as well in case there's any special considerations with IRQs for music users.

Noel · Post by **Noel** » Fri Sep 19, 2008 7:51 am

I assume we are talking about a laptop here.

If it's anything like my old p4 laptop then heat and may be your problem, especially if it seems to runs OK for a few minutes and then starts to crack up. A good clean-out helped in my case, getting all the dust out of the fan blades, heat sinks, air ducts and such. It helped, but didn't fix it totally - just meant it ran a bit longer before choking.

You can find out if over heating/speed stepping is at the root of your problem by repeatedly running a CPU intensive bench marking tool. If the test score gets lower with each subsequent run then you have found your problem.

Another thought, in case that is not your problem.

What irq is your card bus slot (assuming you have one)?

You could try using a card bus firewire adaptor, or use a card bus USB adaptor and disable the on board USB?

mesaboogiewes · Post by **mesaboogiewes** » Fri Sep 19, 2008 7:56 am