To adjust the popunder behavior setting, click on the pencil button at the right from spot name (see pic below):
Frequency Capping - the time gap in which popunder will be showed. (in seconds) 1:24 (86400) means that you will show one popunder every 24hrs.
Sub frequency capping - the number of creatives that will be shown within one capping period. It's set to 1 ad launch by default. If you set it to 2-3-4..., this will mean how many ads will be shown in a row (for each page update), so that 1 click results in 1 popunder, next page update - click and ad launch as a result. If you set it to 0 - popunder will be shown constantly (taking into account the total capping).
In the left panel is a general popunder setting, in the right panel additional settings for custom targets.
Default config
Bind to: parameter sets in which CSS classes will trigger a pop. For example, website element class: .class or id: #myvideo. You can type a few and split with coma: .class,.class2,#video. For a class type such as class="btn btn-danger", replace space with a point: .btn.btn-danger to add to the line. Open up webmaster tools (F12) and point to the element on your website to trigger the popunder. You will see the class name or element id on the right:
Ignore to: parameter sets which CSS classes will be ignored to trigger a pop (the same examples as above)
Popunder kind: Choose from popunder, popup, tabunder, or tab up.
Pop width / Pop height: Size of popup window (works for popup only)
Pop position: Position of a popup window
Targeted configs: In the example above, Firefox visitors will see only one popunder instead of 2 popups which will be triggered by clicking everywhere on the site. You may add as many as you need for any combination of device/browser/country.
Wait for page navigation for next portion: if turned on, the visitor will see the next portion of popunders only after navigation, if Global Frequency Capping expired. For example, you need a popunder to be loaded 1-time per page load/update. Thus, you need to do the following setting: Frequency Capping: 0; Sub frequency capping: 0; Wait for page navigation for next portion: turn on.
Delay: Set up the number of seconds from the page load during which the popunder should not be fired. The countdown restarts every time user navigates or refreshes the page:
Skip first N clicks: before pop will be exposed
Multiple popunders: series setting. Here you may set multiple pops and intervals between them.