[asddingo]

I connect my Windows laptop to my TV via hdmi and the video is normal, but the sound is sped up.

[Plnch]

have you reinstalled your drivers?

[InternalData]

Try giving your laptop's audio drivers an update, go into "Device Manager" for that. Also, right-click the speaker icon down in the taskbar, hit "Open Sound settings," and double-check if your laptop is streaming audio to the correct place.