If you call technical support too soon, you will likely upset the manufacturer as you may ask obvious questions that you should have answered by reading the manual. However, if you wait too long, you could be burning tons of time for an issue that may be the manufacturer's fault (bug, poorly or undocumented issue, etc.).
On the one hand, I can sympathize with manufacturers who routinely complain about support calls that could easily be resolved by the tech spending a few minutes checking documentation. On the other hand, a lot of good techs take a macho but counterproductive approach of never calling tech support until they have exhausted all options over hours, if not days. Frequently, the solution is something that tech support can solve in a fraction of the time the tech took.
So how do you handle it? When you decide to call tech support?