A method and system for providing a content object is disclosed with an in-stream ad unit inserted into the content object for a content object player. The content object is audio and/or video. A media services platform (MSP) knows of one or more in-stream slots in the content object where in-stream ad units may be placed. The MSP queries a display ad server (DAS) to specify the in-stream ad unit, however the DAS does not natively support in-stream ad units in this embodiment. The MSP maps one or more in-stream slots in the content object to corresponding display ad locations. The MSP places the in-stream ad unit into the slot of the content object to create a processed content object. The MSP optionally transcodes the processed content object. The processed content object is downloaded or streamed to the content object player.