Across the road from the theatre was the odeon. The building would be used for small scale performances, and also serve as a council hall From the Wikipedia: a bouleuterion was a building which housed the council of citizens (boule) in Ancient Greece.
It dates from the second century AD, had 900 seats, and a vaulted corridor running under the seats that would be used as a meeting hall in its own right. I could not see the painted walls, they looked to much damaged by moist and growth. The mosaics that supposedly covered the floors had also suffered a great deal.