BROOKLYN - A yearly study from the Riders Advocacy Group has found the subway's B line has the least audible loudspeakers, with only 55 percent of its announcements considered audible.

Subway riders complain that the announcements are often scratchy with a lot of background noise, with one straphanger comparing it to the announcer talking through a tin can. The biggest concern from riders is not hearing if a train is skipping certain stops.

Those who participated in the survey said they have an easier time hearing updates on trains that have automatic announcements. These trains, including those on the 4, 5, and 6 lines, feature digital voice announcements and visual displays, and B line riders said they hope this new technology comes to their line soon.

Despite the B line problems, the survey still found 83 percent of systemwide announcements are easy to understand. Those who are having difficulty hearing loudspeaker announcements are urged to call 311 and notify the city of the problem.