When I sourced my flush mounted t8 4' & 8' fixtures via a local electrical supply house I specified "specular reflectors" they Alone added 20$ to each fixture. Expensive (Cooper Metalux) units, but worth it as my garage man cave is Very well lite with them. "IF" you are Serious ($$) research...
I encountered this very problem. A Ham Radio 'Guy' at work explained to me that I purchased "COMMERCIAL" grade fixtures at a Local Contractor sales store. I installed them and created my own interference problem by doing such. I found that the Cooper-Metalux manufacture offered a Radio Frequency...