Hello Mister. I am having the exact same issue here. I have a Pavillion g7, and it used to work like a charm. Since I installed 8.1 it has a very long (about 1 minute and a half) delay with both, online and stored videos and music. my laptop specifications are:
Product number C3Q78UAR#ABA
WINDOWS 8.1
X64 Based PC
processor AMD A8 4500 ARU with Radeon graphics.
Thank you very much in advance.
Ps. the clean booting didn't work
Ps 2 Sorry about my English. Not my native tongue 