The One M8 rivals a strong second round of competitors like the LG G3 and in India, from the likes of Xiaomi, and then there's Apple, which will be rolling out iPhone 6 in markets soon.

Total third-quarter revenue is likely to fall between $42 billion to $47 billion, in other words, reduced 27.8 percent to 35.5 percent of Q2 revenue, HTC said, compared with $47.05 billion in the same period of 2013.

HTC's Chief Financial Officer Chialin Chang admitted that demand for the firm's M8 has settled at a low level. “In light of the predicted revenue decline, we have to adjust resources appropriately to maintain profitability,” Chang said, adding that the firm will streamline its sales and marketing strategies.

On the other hand, according to Windows Phone Central, HTC has sent out the press invitation, saying that they will release new handset on August 19th. Though there's no further detail of the new handset, it is believed that it will be the Windows Phone W8, sharing the same high specs of One M8.

There's no smoke without fire. The W8 rumors appear to echo remarks made by a Microsoft Executive at the Computex Taipei trade show in June that the company is working with HTC on a new Windows project.