I am having a really perplexing issue with Chromecast. I do not have a dongle but I do have an Nvidia Shield with built-in  Chromecast. I cast to it from the Chrome browser on either of two laptops, one running Win 7, the other Win 10. I’m not sure of the laptop specs offhand, but both are more than capable of normal streaming. The Shield has a wired connection, the laptops are on a wi-fi link that serves only them. 

In addition to the Shield, I also have a MeCool combo device that receives DVB-T and satellite, and also has a Shield clone built in for Internet. This is also on a wired connection. The MeCool is not authorised by Google so does not actually work as a cast destination, but it shows up as a cast device on Chrome. 

Until recently, casting from either laptop to the Shield has worked perfectly. One time the Shield stopped being recognised but this was easily fixed by resetting the built-in Chromecast app. Since then it has worked fine until a couple days ago.

The other day I started getting random issues that don’t make any sense at all to me. Sometimes the Shield is recognised by one laptop or the other, sometimes only one, sometimes both. The Win 10 laptop seems to have the most trouble. For some reason, it seems to see the Shield more often if I also have the MeCool powered on.

When I am able to get either computer to cast, the audio is very choppy. This is a new problem. I haven’t had it before. It seems to be the same on both computers, though maybe worse on the Win 7 laptop. I’m not sure if the video is also affected. I only notice it on the audio. I have tried rebooting and powering down all devices. Also resetting the Shield app. Sometimes this seems to help Chrome find the Shield Chromecast device, but is doesn’t help the choppy audio. 

There is no problem with the wi-fi or the source. If I view on either laptop, the stream is smooth and the audio perfect. I only get the problem when casting to the Shield, about two metres away. 

I also tried casting the desktop instead of the tab. This also used to work fine. This time the audio quality was poor, as if echoing from the bottom of a barrel, but it wasn’t as choppy. 

Everything worked perfectly until it stopped working. I am not aware of anything I have changed. It worked, then it didn’t. The randomness of this is very frustrating. I don’t understand what is happening or why. Any suggestions or ideas would be very welcome. I did look on Google, but the information I could find was not very helpful. One ‘tip’: this just happens sometimes and if you wait long enough it may correct itself. I am hoping for something a little better than that.