Distributed multimedia applications increasingly populate audio-visual mobile and desktop devices. Crucial to the success of is the delivery of quality of service (QoS) which often refers to resource reservation on devices and network links. QoS is usually ensured by an appropriate admission control that determines if another request for resources can be granted without interfering already accepted data flows and processing resources. If an AC cannot be processed or proves to be unsatisfactory, proactive counter measures like resource adaptation may decrease the resource requirements of particular data flows. This paper presents a new methodology for resource adaptation in AV devices. It is incorporated into the UPnP QoS architecture and concealed behind a common set of interfaces. An implementation of resource adaptation proves that the resource utilization is optimized and the QoS can be acceptably maintained even in overloaded conditions.