Edit: After half day, my wife’s Mac started having the same problem. I have then applied the solution that I found in the Apple
Apple Struggling In Royalty Negotiations For Music Streaming Service
Recently rumours have suggested that we may see Apple bring out a music streaming service to compete with market leaders such as Spotify and Pandora but it now appears that this maybe delayed due to Apple being unsuccessful in the negotiations about royalty fees.
Recent reports are suggesting that Apple was unsuccessful after offer to record labels 6 cents per 100 songs streamed which is half of what other competitors are paying such as Pandora who pay 12 cents and is dramatically lower than the industry standard of 21 cents. Apple is not short on cash and many record label executives believe that Apple should be offering close to the industry standard if not higher.
The music service was set to be launched along side the iPhone 5 back in September 2012 but obviously hit some kid of problem. The report also says that Apple wants to integrate its other services such as iAds (Apples Ad platform) and mentions the possible opportunity of bundling it with the year old serve iTunes Match.