Apache problem: delay in response to POST
I'm running Apache (httpd-2.0.51-2.9.2.legacy) on FC2 box. The problem I'm getting is that response to POST requests is quite often slow - client has to wait for tens of seconds, which usually leads to people canceling request and reclicking a submit button. This happens randomly, but quite often (sometimes even once in two requests or so, sometimes a bit less often).
Requests do get processed, so this leads to many double and triple posts on phpBB forum I'm running.
I'm not sure when this started. At first, I suspected the faulty network, but this is now happening when I access from a client on the same machine. I suspect the latest Apache package upgrade, but am not sure.
Sometimes, other requests behave like this, but it's so rare that I don't think it's due to the same problem.
Couldn't find nothing usefull both here and on Google. I apologise if I've missed something.