So engineer has been and replaced the box. 3hours later the robotic sounds came back. I can watch Amazon Fire TV for 3+Hours with no issues, 30mins of VM TV (live or recorded) and I get 20-30seconds of robotic echos.
Thanks for getting back to us with this information.
Sorry to hear it's happened again after your technician visit although it's strange to still be continuing with a new box and changed cable. Is this happening on certain channels and does it happen if you're on the home screen?
Not noticed it on home page as dont generally sit on it for long. I'm wondering if its HD channels. As is so random. I'll monitor over the next few days and look out for any common issues. Have there been any recent (last few months) upgrades?
I have not heard of any updates that have caused this, I also watch mainly HD channels and I have not experienced this issue. Have you tried watching any SD channels to see if it's the same? And are you using any surround sound system?