It would appear that her eagerly-awaited return to music has proved to be all too much for Whitney Houston.

After a week in which the singer was slated for her disappointing comeback concerts in Australia, she flew out of Sydney this morning looking more than a little worse for wear.

She stopped to pose for pictures with fans, who posted the snaps on Twitter this morning, but she looked distracted, her smile seeming fake as she hid behind brown sunglasses.

Bedraggled: Whitney Houston looks unkempt and grumpy as she flew out of Sydney this morning

The 46-year-old singer is currently on tour in in the country playing a number of dates in various cities for the first time in 22 years.

But her great comeback proved to be a huge flop for her Aussie fans, who have been left disgruntled with her performances after spending hundreds of dollars on tickets.

There have been reports of complaints, fans walking out and hundreds demanding refunds on their tickets, some of whom had paid up to AUS$699 (£410) to see the legendary diva in action.

In demand: Whitney poses for photos with a couple of fans

Some fans also complained that Houston sang off key and looked exhausted, with concert-goers even posting clips of her less-than-satisfactory performance on video-sharing websiteYouTube.

The Australian leg of her Nothing But Love tour, in support of her internationally chart-topping album I Look To You, has been smothered in controversy since the first date in Brisbane.

She played the city's Entertainment Centre, where, according to fans, she sounded 'croaky and appeared 'disorientated'.

No pictures, please: She tries to avoid the cameras as she heads off to catch her flight to Melbourne

They claimed that she struggled through the concert, especially with the high notes, and was left breathless and exhausted after just two songs.

And they added that she took a 20 minute break to catch her breath mid-way through the show, get a towel and re-apply her make-up.

She even on her brother, Gary Houston, to sing in her absence before her backing singers then performed an energetic version of one of her biggest hits, Queen of the Night, from The Bodyguard soundtrack.

Disorientated: Whitney performs in Brisbane on the opening night of her Australian tour

Last night she played the Hope Estate Winery in Pokolbin in the Hunter Valley near Sydney to a 12,000-strong crowd and today she jetted off to Melbourne where she will play the

Her Australian promoter Andrew McManus today dismissed the criticisms and said that he was proud to be associated with Houston, whom he called 'an amazing talent.'

And he said to all the fans that had complained about her voice to go and buy a CD if people wanted to hear the diva of 20 years ago.

Prior to the tour and her album release, Houston had spent years battling drug addiction and a turbulent marriage to former R&B singer, Bobby Brown.

She wraps up her Australian tour in Perth on March 7 and heads to France and Britain in April.