asio load varies randomly, same section of project

hi folks,

i’m using cubase 6.01, getting along pretty happily. especially loving the drum editing! one weird thing i have noticed - the asio load seems to vary randomly. i’m not talking about it varies as the song scrolls along, i’m talking about at the exact same point in a project.

for example, i have a test project that i’ve been using to test asio performance on new interfaces (currently using an rme babyface). running through the first verse, the asio meter can be either hovering around ~65, or ~50, depending on what it feels like at any given time. one minute it will be at 50, i could then reboot computer, load the same project, and it will be at 65. or vice versa.

is there any reason this might be happening?

Not quite sure I understand what you’re getting at. But, I notice that certain parts of songs cause more spike than others, usually the start of a chorus where I’ve got loads of parts coming in all at once, could be to do with disk access, or I sometimes think it’s to do with say an autotune plugin suddenly taking CPU power. Generally when I notice this then I start going through bouncing down the multitude of edits that I have because one thing I’ve noticed over the years is that an audio track with hundreds of edits/cuts can make the whole project unstable. So, I bounce these tracks when I’m happy with the edits (and save incrementally so I can retrieve the original edits, and the audio before the edits!).


hi mike,

no i’m talking about the exact same point in the project having different asio loads randomly. not different parts of the project having different loads, which is to be expected. it happened again just now, rebooted computer, loaded project, asio showing 65% through verse 1. before rebooting it was 50… weird.

i don’t know whether its a windows thing. i have the system configured in the usual way, speedstepping etc all off in the bios, various windows tweaks.

i don’t get it.


OK, so what you’re saying is between reboots the CPU meter reads different values in the same part of the song…

Hmm, I don’t know why that might be, I don’t think mine does, but TBH I never look at the meter much except when things start to go wrong, and then I start to simplify things!

There’s one thing that happens for me sometimes though and it’s to do with my MOTU 2408. It loses connection sometimes and I need to reboot. But, sometimes it doesn’t come back after the first reboot so I’d need to reboot again. Could it be that your sound card is not rebooting correctly each time? I try to wait 20 seconds with the wall power off (i.e. no power not even to the PC PSU) before rebooting and that usually makes it all a bit better behaved.


Unless you’re hearing unwanted noise to do with those readings, whether singularly or at multiple points I wouldn’t worry too much. At the same point is a bit curious though.
As the Goyle says use it for reference when other things happen.

The midi flow can be affected, but without much harm, anytime in the computer. In your case it sounds like one burst of midi data at that time is affected by some sort of interference. Could point to a specific cause though but could be many things as well as Cubase itself but could be a specific plugin or, as said, the soundcard.
You could try muting tracks in turn and see if anything changes. Or unloading plugins / FX to see if anything turns up there.

yes its not really affecting anything in practice as my cpu load rarely goes that high, i was just curious as to what the cause might be.

i’ve tried all sorts of things like disabling certain tracks, plugins etc, but it doesn’t make any difference. any load reduction brought about by that is always relative to the initial starting point load, whatever that might be…


perhaps you could install the Cubase 6 updates and have a try again ?

Please also turn any kind of powersaving / overclocking /“under clocking” options off



hi chris, i’d read mixed reports about the updates so stuck with 6.01 for the time being which has been working pretty ok for me. however, i’ll take a disk image backup and install to the latest update and see what happens…

Does the asio load change if you turn a couple of heavy plug-ins off and back on? If I’m not mistaken, Cubase loads each plug-in as a separate process and distributes them over the processor cores depending on load. Since the load on the cores probably varies a bit between startups the distribution might not be optimal every time.
However, this should not need a reboot, the load should change a bit just by closing and reopening the project.


twinoak you may be on to something there with the load balancing. i haven’t tried turning off then on heavy plugs - trouble is, nothings a heavy plugin these days with i7s!

the distribution of plugs across the cores changing from load to load would i think account for this weirdness. thing is - i want it to distribute the more efficient way all the time! :slight_smile:

as chris suggested i’ll update version next couple of days and see if anything changes…

I like the way PT HD shows me the loads on each HD card (I have 3, multi processors on each). And I specifically like the ‘refresh’ button which effectively rebalances the load across the PT processors and cards. It to helps when processing power get a bit short, rather like defragging a hard disk I think. Perhaps we could squeeze more power from Cubase if they offered a rebalancing function? Quite like to see one on my UAD cards too, but that’s for another forum!