Thank you for the comments. Fresh battery, and tests as such.
I don't consider it RF noise at all, just hiss.
And no 60 cycle hum, or anything like that.
Will call at some point and see if anything I can do on my end. Typically hard for me to reach someone by email or phone at Alembic. I don't expect to be a priority though, having purchased a couple sets of old second hand STRE pickups over the years, of course.