Thanks for your reply.

In your cbtime() function, can you comment this line:

this.image.setFromPixbuf(this.pixbuf);

And see if you still getting the errors above or having the memory leaks?

No leak and no error now, but as expected also no image.

In the next test (with setFromPixbuf enabled again), although I added a 3rd image to the filenames array and the images switch nicely all 3, I get the assertion failure message every 2nd image switch and not every 3rd image switch (just to verify that it's not an issue with a certain image).

I'm out of clues now.

Diez