We turned on iplayer last night and found that the series is actually on there (we cannot get sat tv) - quite entertaining so far with some great one liners,watching the (rifle) armed guards paying compliments to officers is especially funny (one of them actually saluted with left hand whilst rifle slung over right shoulder
).
The use of ac/dc songs is quite bizarre as it really jars with the time/place/narrative and as others have said - unnecessarily loud compared to
dialogue 
,seems the fashion with modern films etc - the music is almost always overbearing.
Shame that a decently entertaining series is marred by the choice and volume of 'incidental' music (which is only required at low volumes anyway).