Things never get dull for the country's lone satellite-radio provider. Shares of Sirius XM Radio (SIRI) were flat on the week, closing unchanged at $3.44. The move was just behind the Nasdaq's 0.4% gain. 

There was more going on beyond the share-price gyrations, though. Sirius XM saw the number of its shares sold short decline during the quarter. On the streaming front, Pandora (P) posted disappointing quarterly results, and Google (GOOG 2.21%) came up with a neat way to promote its fledgling Spotify-like service.

Let's take a closer look.

Short people
Stock exchanges publish figures on short interest twice a month, alerting investors on changes in bearish activity. Sirius XM had 297.6 million shares sold short as of mid-July. That's a slight dip from the 318.2 million shares sold short as of the end of June, and it's the first decline since the middle of May, but it's still a big number.

There is no Nasdaq-listed company with a larger number of shares sold short, though that's partly the result of Sirius XM's low share price. Investors shouldn't get too worked up about a big number of shares sold short. It's good to be familiar with the bearish argument, but having a large number of naysayers also improves the chances of a short squeeze if Sirius XM has some good news to announce. A great chance for that to happen will come on Tuesday morning, when Sirius XM reports its second-quarter results. 

Streaming along
Pandora and Google made waves in the digital-music realm this week. Pandora shares took a hit on Friday after the company posted disappointing quarterly results. The metrics were fine. Revenue climbed by a healthy 43%, and adjusted profit of $0.04 a share was solid. The problem in Pandora's report was that monthly active users, hours of content consumed, and its share of the total U.S. radio listening market all declined from May to June.

Pandora stopped reporting monthly metrics in May, so we may not be able to gauge Pandora's month-to-month popularity in the future. For now, the market just isn't happy until Pandora can prove three months from now that its popularity didn't peak in May.

Amping up the coach potatoes
Google's Chromecast has been a hit with consumers, given its $35 price point and the small device's ability to stream Web-based video on TVs. Google has sold millions of the devices since last year's launch. Now Google is offering Chromecast owners 90 free days of its All Access digital-music service. Google charges $9.99 a month for the service that's an on-demand offering along the lines of Spotify.

Google's digital-music platform doesn't seem to have gained a lot of traction, but this move should get a lot of people who are already in Google's ecosystem to kick the tires. It may seem like a desperate move, but offering a free trial for three months is something that could cause trouble for other premium audio services.