Why is Google adding an awful border to my ads?

[oddsod]

Ad units on one of my pages seem to have an ugly, thick, dark green border around the 468x60 boxes and I can't understand why. It's happening on both image and text ads.

The page uses the old code and both border and bg are set to FFFFFF. The page has a white background.

Has this problem cropped up for discussion before? Or am I doing something stupid?

<added>It's happening only in Firefox</added>.

[oddsod]

Nobody else seeing this then?

(If you drop me a PM I could send you a link)

[ken_b]

There was a thread about G testing different borders a while back. Maybe this is just more testing.

[vero]

This may seem silly, but check that there isn't something in your stylesheet that's creating it.

[oddsod]

I swear it's not the stylesheet.

ken_b, thanks for the tip. It may be this thread [webmasterworld.com] you were talking about.

AdsenseAdvisor said:

The border changes that some publishers have noticed on their ad units have been implemented as part of an experiment that we are conducting on a limited number of ad units. Please know that this experiment will run on only a small percentage of selected publishers' ad units. Also, be assured that we are closely monitoring the performance of these ad units, and appreciate your feedback on this experiment.

Hmm. I don't like this presumption of Google's that they can mess with the site colours/design. This completely ruins the look of my page and makes the ads stick out like a sore thumb. CTR is slightly lower but eCPM is a bit higher. It's not about the earnings - it's about taking liberties :(

For what it's worth, I think I've worked out something. It's happening only on ads that are directly under <h2> titles. The only page on my PR6, 15K page views a day site that has borders is the one that has 468x60 units just under two sub headings. So that maybe what Google is "testing".

[fredw]

I swear it's not the stylesheet.

yet you say

It's happening only on ads that are directly under <h2> titles.

Do you have anything in your CSS that modifies how H2 is displayed? For a quick test, disable your CSS and look at your page again. (Make sure to clear your browser cache first!)

[oddsod]

That's right. I don't believe the statements are incompatible.

For one, that page hasn't changed in months and the ads always displayed correctly. Also, other pages have exactly the same code (and <h2>s) but don't have a border around ads. That maybe because there's some text between the H2 and the ad and is therefore outside Google's "test"