D90 Shutter Release Problem

[CASSARIO]

I just recently started having a problem with the shutter release, although Im not getting any error codes, which I seen in another thread someone was getting with this problem.
I purchased my refurbed D90 about 5 months ago and havent had any issues with it til about 3 or 4 weeks ago. The shutter release button will have a delay or just not release about 2 out of 8 presses, until I press it again. I have tested it to check different things and this is what I have found...

1. It will happen with all 5 lenses that I own, so it is not lens specific.
2. I have made sure that the lens is focused and have had it happen.
3. I have put it in manual focus, had it on a tripod so the focus doesnt change and it will not release apon being pressed on average 2 out of 10 times, but it can happen once or 3-4 times consecutively.
4. I have changed many of the menu settings and nothing seems to affect or fix it.

If anyone knows anything about this please chime in, since it is a refurb the warranty was only a 3 month warranty I believe, I have to double check, but Im pretty sure it is up, so sending it to Nikon wont be cheap and I have been holding off. It is more of an annoyance than anything since it doesnt do it all the time, but I have definately missed some good shots because of it not releasing when pressed. I guess Im going to call Nikon and see what my options are. If anyone has any suggestions please let me know. I posted this on someone elses thread but wanted to put it in a seperate thread since it could be a different problem. Thanks.

[zona5101]

Sounds like you have the right approach, call Dr. Nikon.

[sk66]

That really sounds more like a focus issue. Are you sure the camera thinks it's in focus? You can try and change your setting to "release" instead of "focus" to see if that eliminates the issue...if it does, it's a focus issue.

It could also be an exposure issue where the camera is trying to use the popup flash but it isn't working, but that doesn't seem likely.

[kirbinster]

Do you by chance have a grip on the camera? I was having a strange shutter release problem a while ago and finally figured out that if I did not turn the grip shutter release off when shooting landscape that my hand was partially pushing that button which would not allow the main shutter release to operate.

[Azaki]

Also check for the Exposer Delay Mode option is turn off (d10) in the menu) that will dilay the shutter for a second or 2.

[IainM]

I sometimes have this problem, and it's usually a focus thing (low light and using AF). But you mentioned that you put it in manual focus and it still does it so yeah... I dunno.

It could sure get annoying I know. I hope you figure this out.