Bit of an odd issue.
Libreelec v8.95.3 beta Running on an Intel NUC Bean Canyon NUC8I3BEH3 i3 8109U. tvheadend as the pvr service running on a separate server. Problem has been there with all the betas.
Basically, there's one channel on my PVR, (4seven for what it's worth) that suffers from near constant fragmentation. This is a non HD channel. All HD channels perform perfectly and I've not found another SD channel that suffers from it.
If I turn off hardware decoding then the problem goes away, but obviously this then affects the smoothness of fast forwarding/rewinding on the HD channels which is actually more important to us.
This issue does not exist in previous versions.
I have attached log files and a screenshot from tvheadend showing good signal strength.