Cluster-based routes help data transmission in ad hoc networks. Mobile users are organized into a cluster for requiring common multimedia service. However, node mobility does not guarantee multimedia transmission. This study presents a measure of cluster-based route's stability based on a prediction of connection probability at a specific time in future. The selected route is sufficiently stable to enable clustered mobile users to receive time-consuming multimedia streaming in future. Inter-cluster connectivity maintenance schemes, including forward and backward connectivity methods to provide non-stop transmission, maintain inter-cluster links. Finally, analytical and evaluation results indicate that the proposed route chosen based on the connection probability scheme is effective and stable for transmitting multimedia streaming in ad hoc networks.