Small preview in Web Contact sheet are not sharp

When I create a web gallery of selects in C1 - the large previews are sharp and crisp - the smaller (240 px) previews are blurry.  

Several versions back this happened and then Capture One fixed it. Now, the same problem occurs every time I create a web contact sheet (web gallery)

I've written support but have not received an answer. this happens with any camera RAW file - from DNG from drones to RAF from GFX 100s files to Leica DNG files.

Does anyone know of a workaround to this problem?  I have attached two samples - the small gallery view with the fuzzy previews and a larger preview that shows the image as sharp.

Thank you in advance.