Scope PCI cards Sync Source lights blinking -> audio dropouts

[t_tangent]

Scan make decent systems so I am told. A friend has a Scan laptop and runs Cakewalk with a focusrite interface and is very happy with it.

Back to your issue though, yes trying out just the Pulsar 2 is a good idea. Try it in one PCI slot and then in the other slot. Also try switching the cards around after that and see if that makes any difference.

It might also be worth looking at the Windows Performance Monitor. Try selecting a few different processes at a time and have it running alongside Scope so when an audio dropout occurs hopefully whatever is causing those will show up in the Monitor. Its a bit trial and error but may be worth looking at.

[garyb]

background app?

onedrive in windows 10 will do terrible things as it tries to contact its server...

open task manager and watch the detail view to see if you can find the process that is making hay. you should see it suddenly using a inordinate number of cpu cycles when the pops and clicks occur in playback.

[valis]

For the record, RME cards work well even on the USB bus, though to be fair they have some of the best drivers and USB chipsets around. If you were ONLY using the Scope card for i/o, you would find it ran comparably in most cases.

When you are using DSP based effects that include delay lines and other Async features, these require dozens to hundreds of extra 'channels' of data streamed across the PCI bus to the host computer and back again, which is why the cards stress the PCI bus so much, and why they are sensitive to host machine issues and IRQ sharing. It's literally the difference between streaming 18 channels of data for a typical soundcard, and many times that. In most cases even UAD cards don't come close to the bus load a fully outfitted Scope computer places on the PCI bus, and that bus load is 100% time critical.

The upshot? Well you'll notice that UAD cards have excellent audio processing models, but how many synths and mixers do you find there? Scope systems are altogether a unique beast, with unique requirements and a ton of fun when properly tuned.

[garyb]

the main problem with usb is that the controllers are very "chatty" and the Scope hardware can't wait for one to shut up when it needs to talk to the system. Scope streams are realtime streams, so they must be dealt with in a timely manner, or there are dropouts.

that said, usb isn't necessarily the problem with any specific computer. usually, it's bios settings the favor offline over realtime like hyperthreading, or power saving in the OS or bios like EIST, or sharing an irq with a device that won't shut up like USB that makes dropouts, but a background app that is using a lot of cpu cycles that does not need to be on, like one drive can be the issue as well.

of course, i am assuming that there aren't several vstis running with lot's of fx that are simply taxing the cpu. it's pretty easy to over do it.

one or more of the above, otherwise, there's no reason for dropouts...

[valis]

”chatty”... I like that metaphor

[rodos1979]

@t_tangent : Yes, Scan makes very nice machines. I have a Scan 3XS laptop too. I am very happy with both machines and strongly recommend Scan 3XS.

@garyb: I am on Windows 7 x64. No onedrive or any other strange background app. Anyway, if it was an app causing problems then it would make problems with RME too, which is not the case... I was having dropouts with Scope even when listening to Windows Media Player, no vstis, not any DAW app open, not any scope synths, just a simple dynamic mixer with 5 channels.

@valis: Yes, I have an RME Babyface, which is USB. No problems at all there. Not a single dropout!

Update: I removed the XTC card and left the Pulsar2 card in the slot it was (disabling the JMicron controller so there is no IRQ sharing)

There is a bit of an improvement but there are still occasional dropouts even with only the Pulsar2.. Now what?..

[garyb]

no, if it was a background app, it would NOT necessarily affect the RME as well. the RME is a windows soundcard. the Scope card is not.

the wave drivers are subject to random pops in 64bit. this is a known problem. ASIO should be 100% clean.