featured image size different from that defined in functions.php

Hello everyone, I am baffled by this mysterious problem:

I am using Smartline-Lite theme.
The size of my featured images for posts is set in my theme’s functions.php as the default 300 x 200. However, on the front and post pages, the featured images are coming up as 90 x 90.

I checked style.css and other php files, but nowhere is there any reference to a 90 x 90 image size.

I am running the same site offline on my laptop using MAMP for testing purposes. The images here show up without any problem as the default 300 x 200.

The problem is only on the online version. The theme and WP versions are the same, and so are all the other files. I even uploaded the offline files to the online server, but still the same problem.

Any ideas?

URL: http://www.orandanow.com
(You can see the post featured images are like thumbnails now, which they shouldn’t be.)