Netflix buffering despite decent connection on Pi4

Hello,

I am running CastagnaIT's Netflix Add-On on a Rasperry Pi 4 (4GB) in Libreelec 95.3, but I get randomly occuring buffering while streaming in 1080p.

The Pi is connected to the router via cable and we have a 50 Mbit/s connection. Speedtests on the pi itself show atleast 45 Mbit/s at all times.

The same movie or show runs fine on 2 Android devices, a laptop and a PC.

There is nothing else taking away connection speed when the buffering occurs and it is not correlating to a certain time of the day.

My ISP is not throttling netflix either.

The problem occurs either as a "real" buffer (loading circle for a couple of seconds) or the audio and video stream get out of sync until the loading appears. Pausing the show/movie and waiting for several minutes does not change anything. Also, one show or episode runs fine while another makes problems throughout the stream.

Do you have any advise for me?

thank you,
Beda

Quote from lrusak

the RPi4 cannot HW decode when playing netflix. So HW decoding 1080P H264 may be at it's limits.

CPU/GPU loads are at 60-70% or below while watching netflix @1080p. Also I don't think the Pi is limiting as one episode is fine, while the next one buffers repeatedly. I doubt the quality/stress while decoding differs that much from one episode to the other, right?