I found AirAttackHD to be the wifi killer on the vendor rom. Once I played it once privacy inspector/task killer showed the service always running, this resulted in several AVI not playing properly. I was tempted to test it at work and get IT Security to report back on the IPs it was hitting but I want to keep my job. I might ask the question. Also 4k player has a service running. I dont trust apps that run with a service unless they are built in android, yes a tad paranoid.