diff --git a/tools/jbuf/README.md b/tools/jbuf/README.md
index 1abf1638b4..fd52e9e8d9 100644
--- a/tools/jbuf/README.md
+++ b/tools/jbuf/README.md
@@ -10,7 +10,7 @@ How to use
 cd tools/jbuf
 cp env-template .env
 # edit .env
-./generate_plot.sh
+./plot_loop.sh
 ```
 
 - The plots are collected in sub-directory plots.
@@ -18,7 +18,8 @@ cp env-template .env
 Units in the Plots
 ------------------
 
-The variables `rdiff`, `wish` and `n` are given in number of packets.
+The variables `rdiff` and `n` are given in number of packets.
+While `wish` and `nf` are given in number of frames.
 The events "underflow", "overrun", "too late", "duplicate", "out of sequence"
 and "lost" are printed only as dimensionless dots with a `y` value somewhere
 in the middle of the diagram.