We've learned from two sources that AOL VP Rob Irvine, who helped program AOL.com, is leaving the company.

We reached out multiple times to AOL PR asking them to confirm or deny the news, but they have yet to respond.

Rob's exodus makes four high-profile defections from AOL in August.

First we learned ex-Googler Jeff Reynar was quitting for real-time media startup, TLists. Then came news of content czar Marty Moe's long-planned departure. Then we heard about finance whiz Kami Ragsdale splitting for former AOL ad boss Lynda Clarizio's company, Invision.

All this comes after AOL missed Wall Street's earnings expectations for the second quarter in a row earlier this month.

A source close to AOL CEO Tim Armstrong tells us to expect more turnover at the top. This source's theory is that when Tim, a former Google exec, first came to AOL, he brought in lots of ex-Googlers because they were people he knew and he trusted. Since, he's learned that trustworthy people aren't necessarily also competent people.

See also: Meet The Googlers Running AOL