I'm not entirely sure whether this is the right place to ask, but I have no idea where else to post it.
Problem:
At random moments in the middle of a bossfight in 25man raids my UI fully locks up. When this happens all my (de)bufftimers (EBB/Scorchio), my Unitframes (Pitbull3), my castbar (Quartz) etc just freeze. I do still see HP-changes on my MT-frames (Ora) and Poweraura's still displays procs, but everything else just seems to lock up completely. When it's really bad I can't even type in chat anymore. I noticed this happens when my Fubar-PerformanceFU shows near or over 100MiB in Addon memory usage, but I can't check which addon it is specifically as that doesn't work anymore either at those moments.
At first I thought it might be related to recount having collected too much data, or my Pitbull Dogtags which I had changed a few days before it started happening. So I disabled all my dogtags, disabled recount and started reloading my interface after every bossfight in case anything else would be saving up data somewhere. This didn't help at all. The lockups can happen hours after I last reloaded but they can happen just minutes after I did it as well, I can't find any patterns in it except that it only happens during 25m bossfights, I've not had it happen anywhere else.
I did try to disable about half of my addons and only kept those I couldn't live without (which is still a fair few) and it did seem better. I didn't experience any more lockups for the rest of that evening, but the next raid they started again while I was still playing with the same addons as the night before.
I assume it must be an addon problem, but I have no idea how or where to start looking. In case it's needed, a full list of addons can be found
here, I don't have all of them enabled all the time though.
If anyone had any similar problems or could help me fixing it without having to start my UI from scratch (no time for that right now) it would be extremely appreciated.