The scientific researches performed in the past decade clearly highlighted that Quality of Experience (QoE) has become the ultimate measure of service value in this rapidly developing era of technology. Its continuous monitoring is now simply essential and is the key to service success. Subjectively measured QoE is considered to be somewhat unerring, however, several human factors may introduce distortions in the assessment of multimedia quality. Motivated by the phenomenon of cognitive bias, this paper attends the topic of end-user devices; how they may influence evaluation of video streaming quality. We performed an empirical analysis of mobile streaming multimedia quality with 100 participants, and utilized four different subjective measurement scales. Results show that the perception of streaming quality was significantly affected by the phenomenon through cognitive dissonance.