Can't parse these on the ST Jumbo:
30a. Lacking energy, looks up and stares (5).
O-l-S. Ogles?
31a. About to start broadcasting, moving over to one (2,3,3).
I-T-E---. In the air?
3d. Crack on paving stone at roundabout (3,2)
S-T-O. Set To?
Thanks in advance.