Project with PeppyMeter/PeppySpectrum Screensaver Plugin for VOLUMIO

Hi
I installed PeppyMeter Screensaver in my Pi3B with Volumio V2.9 and connected to my monitor through HDMI. I selected 1920x1080 folder.
However, the graphic cannot be fully displayed. The right and lower sides be cropped.
It look like incorrect resolution. But I had checked the file properties are correct.
The normal payback screen also no problem.
Anybody can hep?
Thanks!