Enough with the caps...
For those that have fmodex crashing problem, it is unlikely that you'll be able to get rid of them entirely, you can how ever lower the likelihood of having them. The next version, sc4.1 should run more stable for those that have the fmodex crashing problems. For some, running in d3d mode can help, but the partical effects only work correctly in opengl mode. Software mode has some limits to the max w poly you can have in a map and still have it work, it won't work on some of the more complex maps.
If your wondering what fmodex is, it is the sound engine sc4 uses, pretty much all of the games sounds are played through that. The way they have it implemented in the current version of sc can be pretty buggy for some. It's not used in any other hl mods that I am aware of.
If your getting high ping spikes on the server, try typing rate 30000 in your console to increase your max allowed rate, if your rate is to low you can get very high pings in area of maps with a lot of monsters.
As for the sound spam, if your talking about people playing music or spamming sounds over the mic, you should report that since it's against the rules. There's a thread
here with guidelines on reporting bad players to the admins.