Variation of superframe duration could be a promising way to improve the performance of a wireless local area network (WLAN) carrying interactive multimedia traffic. Most of the studies, however, looked into DCF-based performance improvements of WLAN taking delay and throughput as the performance metric for homogenous traffic. This study looks into the jitter profiles of PCF-based WLAN in transmitting interactive multimedia traffic in a heterogeneous setup. In this mixed traffic environment, the effects on jitter, following variation of superframe and contention free period durations are investigated by simulating a typical mixed traffic WLANs scenario. Results of simulations show that selecting and tuning the CFP and superframe sizes will attain better jitter profiles.