At work, serious problems are often first mentioned in small words.
Just a heads-up : A problem is coming. One small thing : Something important has gone wrong.
A bit of a hiccup : A setback that will cause delay. Teething problems : Faults in something new, which may be serious.
We may have a slight issue : There is a problem. It’s probably nothing, but : This needs attention.
I don’t want to make a fuss, but : A real complaint follows.