No. Uneven movement can occur while video keeps playing continuously; buffering usually interrupts playback while the player waits for more data.
Why this happens
A ball that moves unevenly across the pitch is a different observation from a channel that stops, displays a spinner and then resumes. Motion depends on the frames in the source and how the player and display present them. A stream can arrive on time yet look uneven when its cadence does not sit comfortably with the screen output. Conversely, a perfectly matched display can still pause when delivery falls behind. Treating both symptoms as a broadband-speed problem makes troubleshooting less useful.
Use a long camera pan or a scrolling news ticker to describe what happens. Does movement repeat a small judder while audio continues normally, or does the whole picture stop for several seconds? Keep this distinction in the report. If you try a frame-rate matching feature, use the instructions for that device and record the original setting. Do not change the decoder, television processing and network together; each change tests a different part of the viewing chain and makes the result harder to interpret.
A useful way to work through it
Describe whether playback pauses completely or motion merely looks uneven.
Use the same moving scene to compare one supported output setting.
Keep network comparisons separate from frame-rate or motion-processing changes.