Moisture on interior chimney wall, need advice

Alright, more pics:

Alright, more pics, as requested. I can't get a good shot of the chimney from the roof, hopefully these will suffice.

and 3 more

Howdy. I live in the problem house too and wanted to add a few details.
-First the chimney was tuckpointed, top 13 or so rows re-built, new chimney cap (or crown? the cement thing at top) was added and whole chimney was sealed. This was supposed to fix it, but did not.
-Then the roof and flashing fix as described above.
-Some flashing was also added behind gutter, just in case.
-Then, when a new furnace/AC was installed, a chimney liner was installed and both the new furnace and hot water heater were directly vented outside, whereas before they vented into the unlined chimney.
-After this was done the interior damage was fixed and repainted and it stayed normal looking for over a year, until this spring when moisture showed up again and continues to get worse. Gutters are cleaned frequently.

I'd love suggestions as to who to turn to professionally for a fix, because everyone who sees it says something else and it keeps reappearing. In addition to 3 roofers (none who agreed of course), chimney guys, and HVAC people, two all-around handy men have taken a look and suggested things, we do them, but it returns. I'm beyond frustrated.

Thanks in advance for any input!!

I see multiple issues and any one or all can be causing this and the fact that your roof has no overhang doesn’t help.

What your contractor is calling a cricket isn’t what I conceder to be one. If I was doing it the cricket and flashing details would have looked like this.
http://www.google.com/imgres?imgurl...&ndsp=20&ved=1t:429,r:12,s:0&biw=1154&bih=715 With the exception of instead of using roll roofing as pictured I would have used matching shingles.

The white flashing in the picture is called counter flashing and the top edge of it is installed into a groove cut into the chimney. The lower edge is covering the step flashing, which is not visable. http://www.google.com/imgres?imgurl...1&ndsp=23&ved=1t:429,r:1,s:0&biw=1154&bih=715

The next issue is with the siding terminating into the chimney. Currently the siding just butts into it and your relying on the caulking to keep water out. That area needs to be flashed too. There should be metal behind the siding and out the chimney protecting that corner and then the siding butts into that flashing.

If all flashing is installed properly the siding flashing and the roof flashing would be integrated together so there is continues protection of that intersection from the roof and down the wall.

This is especially important in your situation if you combine the facts that you have no overhang and the gutter pitched toward the chimney. That’s a lot of water in that corner during heavy rains.

I think the issue may be that the gutter/downspout is backing up and water is getting up under the flashing and running down the wall.

I’d remove the gutter, have it pitched the other way and have all of the siding and roofing flashing details reworked.

You need someone that’s well versed in both roofing and siding.

You also have some mortar that need attention.