Cryptic crossword No 2,003

Across

1. Although hospital room gas... (6)
2. ...is ten and four, it's free unto circulation (8)
3. Extent to may involve pH somewhere? (6)
4. Disable, as well as switch. It’s a common IT fix (3,3,2)
5. Spleen flush ruined good service quality (11)
6. Approve goodbye? (4,3)
7. Initial hook up stops group of musicians from becoming a master (7)
8. Epic creator at sea to give back (11)
9. Union starts everything, ends without first two odd bits of finance (8)
10. Produces profits? (6)
11. Rep sex if junk begins a lot of things (8)
12. Show off gold joint. (6)

Down

1. An feud perplexing? One can hear again! (6)
2. Chop fees of dilapidated restaurant (6,4)
3. Pirate speak ending somewhere in the mid-west, then down south. (8)
4. Dumb dish stirred religion (8)
5. Filipinos speak to catch a collection of tree trunks (8)
6. Whirlpool a famous Grant? (4)
7. A pinch of new single, nothing (4)
8. Existence of repetitions from start to end (4,6)
9. Ideally in golf, every tool is an illusion (8)
10. More unfavourable for most of promotion ending with backwards quality (8)
11. James May in Japan cuts first quarter of hour with human enclosure, or part thereof (3,3,2)
12. Decision of joy with the male French songbird (6)
13. Clamour and shout in agreeance to congratulations online (4)
14. Feel around, run! (4)