COME TO think of it, Einsturzende Neubaten did seem to be an unusual choice of support band for Sleeper. And sure enough, the metallic clangings we could hear at the Southend Cliffs Pavilion on Tuesday, 20 minutes after the support act was due on, were not the sound of German avant-garde industrial terrorists; they were the sound of a line of green-jumpered security men, hurriedly assembling a barrier between the audience and the stage, a barrier that had arrived at the venue several hours late. It's the kind of technical hitch that could happen to anyone, but it did seem symptomatic of the way things are currently going for Sleeper.

Sluggish ticket sales have shunted five of the gigs on this tour to smaller venues, and cancelled two of them altogether (the Cliffs Pavilion was only three-quarters full, so the barriers were hardly necessary). Sales of the band's third album, Pleased to Meet You (Indolent) have been just as slow, and the band's American record company has deemed the album not worth releasing over there. Naturally, the music press have wasted no time in rubbing a veritable Dead Sea into Sleeper's wounds.

When the technical hitches are unhitched and the show starts, it appears we may have rubbed too soon. The theme from The Magnificent Seven gallops from the speakers (an odd choice, as even with tonight's extra musicians, there were only six people performing), and the optimistic words "The Beginning" are projected in block capitals onto a curtain. Suddenly, the curtain has disappeared, the band are ripping into "Firecracker", and their name is flashing behind them in red neon. If this is Sleeper's last stand, they're going down with all guns blazing.

Then the vocals start. Sadly, they're the worst vocals I've heard from someone who has "singer" on their passport since Ian Brown's caw nearly evacuated 1996's Reading Festival. And at least Brown had some notion of how to carry himself with grace and purpose onstage. Louise Wener hardly sings at all, but squeaks and shouts breathlessly; if you close your eyes you can imagine you're hearing the last, gasping cries for help from a shipwrecked waif who has been treading icy water for hours. At the start of "Superclean", her voice hunts high and low for the right note, and from then on, the opening illusion that all is well in Sleeperland is dented beyond repair. It doesn't help that her first words to the Southend audience are to greet them as "you Sheffield posse".

Still, there was enjoyment to be had, mainly from imagining how the songs could sound in someone else's hands (and mouth): Wener does have talent to spare as a songwriter. Each track has as many hooks as the average football-club changing room, and the lyrics depict the slow poison of a stagnant relationship so vividly that you can't help speculating whether Wener writes them with an ex-boyfriend in mind (such as Sleeper's guitarist, Jon Stewart) or her current one (Sleeper's drummer, Andy Maclure).

However, when you hear these songs ticking along at the same, rigid disco pace, one after another for an hour and a quarter, they begin to blur into one long Blur pastiche. The band just don't have the range to give each tune an identity of its own, particularly not with tonight's murky sound quality. Three times I wrote a song title in my notepad, only to scribble it out a minute later when the chorus came along.

Sleeper were never what the American film business calls a sleeper hit, ie, an unlikely, unhyped outsider that tiptoes past the blockbusters. At the start of their career, in 1994, iD magazine crowned Louise Wener "pop's wildest, newest rebel". Her marriage of literate suburban vignettes and New Wave guitar riffs was the essence of Britpop just as Britpop was pronounced the thing to be. But the "pop" half of that composite decrees that you're only as good as your last single. The public are always waiting for something different - something new, if not wild and rebellious - and Sleeper have hardly changed. At Southend, Wener was even wearing the same black cropped top as she had on on the sleeve of 1996's The It Girl. A band such as Theaudience can't be said to be any better than Sleeper, but it's their turn for the acclaim and the radio-play because they have one thing that Sleeper don't: novelty value. And, of course, a proper singer.

For a more confident assertion of girl- power, I'd recommend Ani DiFranco. She is just 27, but has already released 10 albums on her own independent record label, Righteous Babe (the latest, Little Plastic Castles, is out now). She has a large and fervent following in America, most of whom seemed to have made the trip over to the London Forum last Saturday, where they whooped and clapped at every barbed line of her and her band's vegetarian-coffeehouse folk-funk.

Franco's acoustic guitar playing is nimble and spiky (imagine Loudon Wainwright after six double espressos) and her lyrics, both personal and political, are fiercer than you'd expect from someone who turns out to be such a kooky chatterbox. On CD, she could eat Alanis Morissette for breakfast. Live, she's a giggling, gulping cross between Zoe Ball and Annie Hall, with All Saints's dress sense.

Her live set didn't pack the emotional knock-out punch of 1996's astonishing, powerfully raw Dilate; her anecdotes went on a bit; and many of her lyrics were hard to make out if you were one of the unfortunate few who didn't know them off by heart. But DiFranco is still one of the most rewarding singer-songwriters around, and twice as insightful as Jewel. She deserves to have more British fans. It would help to reduce the percentage of whoopers in the audience if nothing else.