I'm running opera 58.0.3135.53 in gentoo linux, and I'm having trouble playing pandora. The site loads, but after a minute or so of silence it says that it's having trouble playing.
There are a lot of posts out there concerning issues with pandora in opera for linux, but after a lot of searching none seem to match my issues. A lot are older posts that suggest turning off opera turbo. I've tried this, no effect. There are also posts where the culprit was issues with playing flash. I'm able to play flash on other sites, although I typically have to right click to allow it.