I never get these issues myself anymore, I really do not know why this keeps happening to some of you, if anyone knows what it might be, feel free to send me a PM!
The only thing that is noticable for me is that it is either busy (multiple people browsing around or logged in) or after a great while that the forum seems to be dead and non active (and me being the first one bringing back to life again, sort of speak).
It doesn't seem to matter which OS, which browswer etc. The only thing i can't change (well i can but imho besides the point) is my point of origin.
As for the captcha, that is built into the forum software, and yes, it might be hard to read sometimes, but if I make it easier, we would get more spam bots and then people would complain about that instead.
I understand but sometimes it is nearly impossible to solve because of the bad picture quality. On a normal peecee i can zoom but that feature doesn't seem to work for tablets/phones. Not to mention that depending on the orientation of the phone/tablet the captcha widget present itself outside the visible area of the screen (only the last column is visible, first 2 columns are off screen).
Not expecting a solution rather that you are aware this can happen. Perhaps something to look for when a new release is available so that you can browse through the change-log(s) to see if it is addressed or not (in case you're using a standard feature that causes it).
PS: oh before i forget. Somehow everytime someone "takes a look at things" the forum site speeds up considerably. Even to an extend that i know for sure someone is being screwed when compared to every day usage of the forum. Right now these forums are responding superfast. So fast that i'm sometimes pinching my arms and slapping my face to see if i'm sure i saw things go that fast.