Freeview HD set-top boxes and televisions are available. To qualify for the Freeview HD logo, receivers will need to be IPTV-capable and display Freeview branding, including the logo, on the electronic programme guide screen. The Freeview HD trademark requirements state that any manufacturer applying for the Freeview HD logo should submit their product to the Digital TV Group's test centre (DTG Testing) for conformance testing. On 2 February 2010, Vestel became the first manufacturer to gain Freeview HD certification, for the Vestel T8300 set top box. Humax released the first Freeview HD reception equipment, the Humax HD-FOX T2, on 13 February 2010. It was announced on 10 February 2009, that the signal would be encoded with MPEG-4 AVC High Profile Level 4, which supports up to 1080i30/1080p30, so 1080p50 cannot be used. The system has been designed from the start to allow regional variations in the broadcast schedule. Services are statistically multiplexed bandwidth is dynamically allocated between channels, depending on the complexity of the images with the aim of maintaining a consistent quality, rather than a specific bit rate. Video for each channel can range between 3 Mbit/s and 17 Mbit/s. AAC or Dolby Digital Plus audio is transmitted at 384 kb/s for 5.1 surround sound, with stereo audio at 128–192 kbit/s; audio description takes up 64 kbit/s, subtitles 200 kbit/s and the data stream, for interactive applications 50 kbit/s. Recording sizes for Freeview HD television transmissions average around 3 GB per hour. Between 22 and 23 March 2011, an encoder software change allowed the Freeview version of BBC HD to automatically detect progressive material and change encoding mode appropriately, meaning the channel can switch to 1080p25. This was extended to all of the other Freeview HD channels in October 2011. To ensure provision of audio description, broadcasters typically use the AAC codec. Hardware restrictions allow only a single type of audio decoder to operate at any one time, so the main audio and the audio description must use the same encoding family for them to be successfully combined at the receiver. In the case of BBC HD, the main audio is coded as AAC-LC and only the audio description is encoded as HE-AAC. Neither AAC nor Dolby Digital Plus codecs are supported by most home AV equipment, which typically accept Dolby Digital or DTS, leaving owners with stereo, rather than surround sound, output.