Apple’s effort to license a proposed online radio service, which the press has dubbed iRadio, is being stymied by at least one of the major music companies, multiple industry sources have told The Verge. Apple’s negotiations with Sony continue to drag on and that the electronics maker could hold up the launch of what sources say will be a radio service similar to Pandora, the internet’s top webcaster, but offer more on-demand listening features, such as fast-forwarding and rewinding. Any delay of iRadio could hand one of Apple’s chief rivals an opportunity to beat it to market. In recent months, Google has pushed hard to acquire licenses that would allow the company to launch a Google Play-based subscription music service sometime this summer, numerous industry insiders say. That service is expected to be more akin to Spotify and offer on-demand music listening. Google’s I/O conference is next week. That certainly would be a good place to unveil a new Google Play music service.