Was wondering if when more channels became active between different channels/apps the soundbar was popping as it changed mode or something. Even though sound bars are generally stereo you can feed them surround signal.
I thought popping of this nature was usually current/load discharging.
Are you using e/ARC at all? Sometimes that signal can cause a noise, at least it did for me a long time ago, just thinking out loud possibilities.
my soundbar has a choice between stereo and surround sound although like the STB I had it set on stereo, besides the issue only arises with the apps at the start of each programme ,at the start of each add and when the programme recommences
My soundbar supports ARC but not eARC whereas my TV supports the latter
After having swapped from stereo to surround, the issue seems to have resolved itself for now. Many thanks for the help
Lovely stuff!