I've noticed a number of quality issues when exporting jpegs out of Indesign - so much so that I usually export as pdf first and rasterize in Photoshop. But that was mainly poor type aliasing-this looks like encoding problems, which I'm not able to duplicate.
As a stopgap, would pdf-rasterize work for you?
There are quality problems with placed images that are then exported as JPEG. The solution is to export as PDF/X-4 and open into Photoshop. See #8 in this thread.
If you are using OSX this AppleScript imitates the JPEG export dialog but creates the JPEG via PDF.
I recommend always to export PDF/X-4, open that in Photoshop and make there the JPG, it will cause better quality.