Im using IE 11 on windows 8.1 and the time always starts are like 16:45 ~15mins off atm.
I refresh and it does back to 16:45. Sometimes this value varies though.
 

I wrote it to retrieve the current server time. I believe (it's been a while), enriched wisps spawn every 20:00, yes?

 

Once it gets the server time (GMT), it compares that to your local time to count down. So if server time is 12:05, and my clock is behind by 2 hours and 3 minutes (10:02), it takes that difference into account and then uses your PC time, going off at 10:17, 10:37, 10:57, etc.

 

There are only three reasons the timer would be off at all:

1.) Our server time doesn't match Jagex's. In which case, we'd only be off by no more then a minute.

2.) Once server time is retrieved, the PC clock settings change.

3.) The wisps aren't spawning correctly on the 20:00s.

 

Maybe I'm not understanding your issue. >.< Better yet, from a coding perspective, I don't understand why. I just tested it and when it was at 7:25, I refreshed and clicked start again and it correctly displayed ~7:20.

 

:(.