How to use iqzip?

My station saves all IQ files to my Dropbox account. To save storage space and bandwidth, the IQ files are compressed with xz.

Now that iqzip is available, I thought I’d see if I could switch to iqzip instead of xz. I compiled and installed the iqzip library, and the iqzip example app. I then tried compressing a wav file:

~/iqzip/apps/build/iqzip 4060852_NANOCONNECT-2SAI-1.wav 4060852_NANOCONNECT-2SAI-1.wav.iqz

The result was a slightly larger file:

-rw-r--r--   1 pi pi  63M Dec  7 15:41 4060852_NANOCONNECT-2SAI-1.wav
-rw-r--r--   1 pi pi  64M Dec  7 15:42 4060852_NANOCONNECT-2SAI-1.wav.iqz
-rw-r--r--   1 pi pi  43M Dec  7 15:40 4060852_NANOCONNECT-2SAI-1.wav.xz

I expected a file that would be smaller than the original file. Maybe not as small as the xz file, but I expected some sort of compression.

Is this not the right way to use iqzip?