Just switched over to using Cubase and I have been having an issue with recording. I use the guitar amp simulator, Amplitube and the Mbox 2 as my AI. If I set the buffer size to 512 to reduce all of the delay, when I go to record another track the one I just recorded becomes heavily distorted and grating. If I switch the buffer size back to 4096 then the track is normal again. Not sure how to at the very least help this issue or if it can even be fixed but my PC specs are pretty good and I have never had this issue on other DAWs. Thanks
Hi and welcome,
Could you test your system by using LatencyMon utility, please?
Btw, Amplitube his very CPU hungry. Of course, you can always freeze already recorded track(s). Or you can use Direct Monitoring, if the Audio Device supports it.
Alright, I tried out LatencyMon and these were the results I was getting after about 20 minutes or so.
Current measured interuppt to process latency - 98.6
Highest measured interuppt to process latency - 732.6
Highest reported ISR routine execution time - 704.52
Highest reported DPC routine execution time - 981.82
Reported total hard pagefault count - 21589
those latencymon numbers aren’t great and the mbox doesn’t have great drivers but I though it should allow you to play at 512 samples.
I assume the VST performance meter is pretty high when you are using Amplitube ?
can you post a screenshot of latencymon ?
and what are your PC specs ?
These fourms won’t seem to let me embed images so I’m not sure if I can post an image.
My specs are:
AMD Ryzen 7 1700 - 3GHz
16 Gb Ram
GTX 1650
Gigabyte AB350N motherboard
try it now 
thanks - that’s not horrendous - although it’s only 2 minutes in.
I don’t think there’s anything showing on latencymon that is causing ‘constant’ glitching.
Are you using ASIO guard ?
what that does (well not really but it’s a good way of describing it) - is puts the buffer up very high for recorded tracks or tracks that are NOT in ‘input monitor’ - it’s a great way of saving CPU/ASIO power
Yes it was set to high
ok - is the existing recorded track set to NOT input monitor - that would mean that ASIO guard wouldn’t work.
This is the the input monitor button correct?
if so then yes it is set to not input monitor
that’s the one (the little speaker icon) - but also click the red one too - that’s the ‘record ready’ one…also disables ASIO guard.
Alright both are deselected but there does not seem to have been a change yet
Odd that turning off input-monitor and rec-ready doesn’t have any effect, with ASIO guard on. Normally drops the ASIO performance meter a few ticks on a CPU heavy track.
in that case we may well be hitting the top of what your CPU can do. I assume the VST performance meter doesn’t look very healthy either ?
Have you tried it in a totally new/blank project ? just in case ?
Also you can try deleting (backing up!) preferences …although that really is clutching at straws.
Alright I tried creating a blank project and that really didn’t do anything but what is odd is that when I was opening up the performance meter it really didn’t look all that bad and Task manager is showing my CPU usage is quite low so really not sure about this one.
yes -that CPU meter looks good
is that with Amplitube ?
Yes, one track with nothing but Amplitube running
that’s pretty good 
what buffer ? - and is it playing without glitching ?
I have it set to 512 (since thats the buffer size that gets me a low-enough latency to play) and there is still quite a bit of glitching
and the performance meter is like the image you posted ?
(and can you reset the ‘red’ overload button)