I have a very similar system to yours Bob
i7-4790K @4.00Ghz
32GB of RAM
WIndows 8.1 Pro x64  SSD hard drives and all latest windows patches and drivers etc
And also get a round trip latency reported at 9.8 ms on 128 ASIO Buffer Size.  The only real differnce I can see is your record / playback buffers of 512k.  How do I check what mine are as I can't see them in preferences.
 
Is this the bit in aud.ini you are talking about?  In which case mine are 256 which could be the problem
DiskBufSize=256
DiskRecBufSize=256
 
I can regularly get my 1818vsl to pop and crackle even when using 2048 asio buffers during mixing, even after I've frozen any memory heavy Kontakt patches etc.  Is there anything else I need to change because it drives me nuts

slartabartfast
The issue is not usually with Sonar per se but with the driver for the device. Some audio hardware does not play well with USB 3, even though the specification says that USb3 should be backward compatible with USb2. A possible workaround is to physically attach a USB 2 device to a USB 2 hub before plugging the USB 2 hub into the USB 3 socket. The best advice is to not attach a malfunctioning USB device to a USB 3 socket in the first place. If possible try the device in a dedicated USB 2 socket and test to be sure it works there.

Thanks slartabartfast...

I'm aware that this isn't an issue specific to Sonar as I've come across it many times... I'm just trying to find a way to work around it...

I would immediately move it to a USB 2 port if one was available, but this nachine only has USB 3...

So first I will try adjusting the dropout value, then If that doesn't work I will try forcing the port to become a USB 2 port...

It might take another day though as I might not be able to get to it today... I'll post results for sure!

Keni

P-Theory
Not that it helps but I've been using a 1818vsl for around 3 years now and I'm really not a fan, the drivers suck on it.  You have to treat it with kids gloves.  As per the Presonus website I found that uninstalling it and reinstalling it on a USB2 port and only using the USB lead that came with the device helped but it still isn't great and runs out of steam pretty quickly when it comes to latency.  I've just tried editing the aud.ini file as per the suggestion see if that makes a big difference but I'm seriously considering swapping it for a focusrite when I get chance

Thanks P-Theory...

I've been running the 1818 for a year with no problems on a USB 2 port. I don't know what's causing your difficulty as its been fast and solid as a rock...

I did discover difficulty running it with a very long USB cable, but other than that it's worked well on 3 different machines I migrated it to..

I've used the focusrite and it's a good gadget but if you use the FireWire version, be careful as it is touchy around wifi cards...

Keni

robert_e_bone
I have had a Presonus AudioBox 1818VSL for several years now, as well, and never have issues with it - Windows 8.1 patch current, with firmware and drivers up to date.
 
Perhaps there is maintenance to yours that needs to be applied? (I also run mine in a USB 2 port)
 
Bob Bone

Thanks Bob...

I hope P-Theory can resolve his difficulty. I've found the 1818 to be very reliable...

Keni

Well i changed the disk buffer as per Bob's suggestion so lets see what happens but I do run some pretty heavy sessions 100+ tracks with 2-3 plug ins per track

P-Theory
Well i changed the disk buffer as per Bob's suggestion so lets see what happens but I do run some pretty heavy sessions 100+ tracks with 2-3 plug ins per track

Not surprising you run into the limitations...
Though I know there are others who run projects that large, it's demanding on any system..

I've got dual quad core Xeon 3.4 (?) GHz processors and start feeling the pinch at less than 30 tracks... I do use a number of vsynths though, but still...

Keni

Update...

Nothing is helping.

I increased the dropout value to 750 and even to 1024... Still getting dropouts...

I tried to disable USB3 only to find two things... It could only be uninstalled, not disabled on this machine, but even more frustrating is that 4 of the six USB connectors are USB2 including the one be been using...

I disabled all anti-virus/adware software... That didn't help...

Then I disabled all Bluetooth and WLAN devices in device manager... I had already disabled all the high def audio stuff... That didn't help

I also tried changing the dropout value back to 250 with each of these variations...

Still getting dropouts! Why should this be such a problem on this machine? I've run it with no problems on two other machines... I don't get it...

Maybe the cable? What differences are ther to a standard short USB printer cable?

Stymied and ran out of available time...

Anyone think of anything else I might try? The machine is an i7 quad 3.4 with 8G RAM... Win7Pro

Thanks...

Keni

It may be a job for LatencyMon http://www.resplendence.com/downloads

scook
It may be a job for LatencyMon http://www.resplendence.com/downloads

I've not used this before.

In what way will testing latency discover the dropout cause?

There may be other software running on the laptop which is interfering with it's ability to run a DAW.