It does sound you have some kind of intermittent interference going on.
If you are happy to, try this test.
Would first suggest trying the restart of your Sky Stream box
Go to Settings>Systems Management>Resets & Updates
Select Restart device
Your Sky Stream puck will perform a reboot. It will take a few minutes to complete.
Once that restart is complete, and you are sat on the Sky Stream homepage would the suggest doing a good hour or so test.
Launch Netflix via voice on your puck, and do the Netflix network test;
In Netflix, scroll down the left menu to Get help. Choose Check Network.
Once that speed test is complete, do not exit Netflix, but say in the puck remote using voice a channel like Sky Sports cricket, Sky Atlantic, Sky News, Sky Arts. Please choose a Sky channel.
Watch that channel for about ten minutes.
Say Netflix using voice in your puck remote again and do another Netflix network test.
Repeat as above using voice switching between channels and Netflix for a good hour or so.
Making note of the speed test results.
Would suggest also in the other switching, choosing other channels like non Sky ones for the test, your choice.
Do not try the Sky Sports Main event channel or the Sky sports live sync channels.921/922 for this test
Let us know the reports.
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