Cubase hangs on startup and freezes mid-project

Win 10 Pro user (22H2, up to date) here with Cubase 12.0.70.

Generally had a very stable installation over the last few months but yesterday after working some hours on a project and closing Cubase, it started to persistently hang on startup, mostly during the control room initialization stage, sometimes during other stages.

There were no self-initiated config changes to the PC to my best of knowledge. Tested all usual options (disabling 3rd party plugins, disabling prefs), all to no effect. As I checked Activation Manager, I noticed at one instance that my licenses weren’t showing correctly so I figured it’s probably because of the license API not responding properly and went to bed. And sure enough, Cubase worked again this morning.

However, this time the project froze mid work, and restarts showed the same behavior as before.

Nightly freeze dump from yesterday:
Cubase 64bit 2023.12.27 (663.9 KB)
And from today:
Cubase 64bit 2023.12.27 (1.3 MB)
Cubase 64bit 2023.12.27 (665.5 KB)

Any pointer appreciated if it’s me or the licensing server.

Also, Cubase 11 showed the same behavior when I switched to it.


Don’t believe it’s licensing anymore as the problem persists, and occasionally I can work for hours only to have the project freeze suddenly, and from time to time I cannot even start Cubase 12 at all. I have meanwhile updated all plugins, removed changes to the power plan, but the issue keeps appearing.

Again, appreciate any help/hint.


[EDIT: owlplug doesn’t report any crappy VSTs, and running either Cubase 12 or 11 as Administrator has no noticeable effect.]

Okay, I seem to have isolated the issue to something on the network: the wait chain in process explorer seemed to point to some thread inside Cubase waiting on network I/O.

After disconnecting the computer from the network, both C11 and C12 opened and closed various projects and themselves fine multiple times. After reconnecting, the issue reappeared.

Again, I don’t recall any changes to my LAN or ISP configs so I am still somewhat at loss even though I have half a workaround…

Making progress and documenting for others who may come across a similar situation: diving into Windows event logs close to the random moments in times when the freeze happens, it appears to be down to a maxed out performance diagnostics log file deep in the inner workings of the OS. (See e.g. here or here describing similar issues with non-predictable timing.)

I resolved it by enlarging the max log file size in the registry as described in the second article. As to why the log actually grew beyond the 20M default size I am not yet sure totally but first indications seem to point to power scheme changes which we know that Cubase also makes use of and is sensitive to.

I will research further and monitor the situation to understand whether the resolution is more than just a workaround .