The unclued lights are of a kind and all have to be ignored in the completed grid.
 

Across

1    Fortune-teller worried small company chairmen. Right! (11)
7    Party goer often over the clutch (3)
11    Spike, I look anaemic! (6)
13    Prize stone cut with edge of blade (7)
15    Become liable to back police force and its patch (5)
18    Similar to a story about Bartok’s finale (5)
20    Outline is almost correct (6)
21    Sleep on board – records on film? (5)
22    About one, delivers a flower (7)
29    European birds in the housetops? (5)
30    Evil demon – one unattached and tense (6)
34    King leaves sophisticated city dweller...