Also known as lag spikes, or FPS drops, or frame stuttering, this annoying problem doesn’t happen only in Valve’s Source engine, as I’ve experienced, but also in GoldSrc(yeah, the Half-Life 1 engine). A gif will best explain this phenomenon:
You can imagine that if in single player this is super annoying, multiplayer games like CS:GO are unplayable.
Searching for solutions I’ve found out that a lot of people experienced this trouble. Here’s a Reddit thread where the OP says he solved it by letting OBS record all the time. Somebody left a comment suggesting that leaving the media player on all the time is also a solution.
In this 2009 Steam thread a guy details how whenever there are sounds playing in-game the ping spikes. His solution was to turn off a Windows service called “Multimedia Class Scheduler”. But on Microsoft’s site this service is described as “enables multimedia applications to ensure that their time-sensitive processing receives prioritized access to CPU resources”. Odd solution to an odd problem? A lot of people point to this thread btw for solving the issue.
In some other Steam thread I can’t find right now somebody said that CS:GO( implying the Source Engine) is badly optimized for multicore rendering. I do have an i7 which has 8 threads, so I thought I’d follow the thread solution and set the affinity of the csgo process to one “core” in the Task Manager. It didn’t work.
Then I noticed that all those threads had something in common: at least one person said complained it had something to do with sound.
So I remembered that I’m actually using a Bluetooth speaker on my laptop. Turned that off, bam! GoldSrc and Source engines are back to normal. I’m sad to say that this probably isn’t a universal solution, as I’ve experienced lots of problems with the Dolby Digital Plus sound drivers on Windows, so this thing is a combination of either bad drivers or bad compatibility between drivers, Windows services and engine implementation.
At the end, the really odd thing is that while all these games suffered from stuttering, HL2:EP2 did not. I have no explanation.