Lately my bids haven't gone through.
Today I have a bid for tonight at 22:14MEZ (10:14PM)
I have set the timing to bid 3 sec before ending.

At 10:14MEZ (10:14AM) the bid was set.

Where is the problem?
Is it MyIbay that have wrong time on their servers or is it a setting I can set?

I had an update yesterday due to eBay changes on some auction's pages.
Seems like you set your snipe while this update was implementing.
I'm very sorry that your snipe fired like this, but this issue was taken care of since yesterday and everything should be okay.

You can try to cancel your bid and leave the snipe working.
Please let me know if you still have any problems.

P.S.: I would not recommend using 3 seconds for your snipes as it may not have enough time to snipe due to network lags or other external issues.
The recommended value is around 5-6 seconds.