My iMac is hardwired. I tried using my phone with WiFi and it shut off after about 5 min and said my wifi was not connected to the internet. I tried hooking the phone to the mac and it started to play and then switched to a completely different screen????I'm thinking I may have an internet issue. My wifi has not been working very well lately...I just assumed it was because I was in a different room but maybe not.
Thanks for your help...I will research the internet thing...don't know why the computer would only act up when watching videos..