Retail sales of satellite radios continue to be sluggish, and a general lighter trend in retail traffic suggest that “should this trend continue into mid-October, it may very well be appropriate to assume retail interest in satellite radio has waned,” according to a recent survey by Bridge Ratings.

Activity for the week before Sept. 27 was flat compared to the previous week and down 29 percent from Labor Day weekend statistics, according to the audience measurement service.

Two hurdles cited by Bridge Ratings were costs of the service for the college-age market and overall lack of consumer awareness about the benefits of satellite radio in comparison to terrestrial, Internet or traditional radio.

Bridge quoted Bank of America analyst Jonathan Jacoby as saying “poor retail trends and Big Three auto production cuts” make it hard for the car companies to “bail out” XM Satellite Radio and Sirius Satellite Radio from what looks to be weakening subscriber add numbers; Jacoby thought the number of receivers being sold at retailers “may peak” this year.

Bridge said XM is expected to add more than 300,000 subscribers in the third quarter, compared to about 450,000 for Sirius, representing “a real turnaround, [one] in favor of Sirius.”