This is a known issue in LabChart for Mac version 8.0.10.. The import sampling speed values are being assigned inversely from what is displayed in the import file sampling speed pull-down list except for the default selection of 1000 samples/sec, which behaves correctly. For instance, a selected sampling speed of 2000 samples/sec is actually being imported as 500 samples/sec, and a selected sampling speed of 500 samples/sec is actually being imported as 2000 samples/sec. This behavior proceeds in the same fashion up and down the sampling speed pull-down list.
Note: this issue was corrected in LabChart for Mac version 8.1.