[James2001]

If it was made in SD, which is likely (though 2007-9 was the back end of SD drama production) and it's a recent acquisition, it's likely suffering from the same de-interlacing and zooming issue we've mentioned on other shows. The latter will be less noticable due to it being shot on film, but it will still be reducing the picture quality.

Edit: looked at the most recent episode on UKTV Play, and yeah, it looks pretty awful. Very soft and blurry, and clearly zoomed in. There's no way something from 2009 should look like that, even if it was made in SD.

The end credit text looks awful, and you have the telltale copyright strap very close to the bottom of the screen

   

Finding a video on YouTube, while the quality's poor because whoever uploaded it shrunk the credits into a box to show off their channel's logo, you can see the copyright strap is a lot further from the bottom of the screen