What audio format does the Sonos app show is playing out of the Beam when watching TV via Sky? Stereo PCM? Dolby Digital?

What is the audio setting on the Sky set to? Also be sure to turn off any dynamic range audio setting on the Sky box.

Try retuning your system through the app. I had stuttering and skipping audio and after countless hours trying to fix it including reprogramming the TV from scratch I activated “True play” option and after I performed this as if by magic the sound came back better than ever on every option. I did contact SONOS but I believe I was emailing an inexperienced operator in support who wanted me to reprogram the channels on the router which was absolutely nothing to do with the issues I had described 

Thanks, I'll try what you've suggested when I return home at the weekend. 

Hi Steve, I hope the fix works for you. You describe the same issues as I was experiencing so it should fix your problem issue. Please let me know how you go on 

regards Geoff.