Idea to reduce RFI

I live 1 block from the main mobile communication tower. That my speakers has pickup some radio channel though its only audible with my ear next to the speaker.

i am looking for any idea to reduce this kind of RFI. how bout an ferrite core? ERS paper? shield interconnect? shield power cable? which is most effective way as read somewhere in the forum that shield PC for amp causes dead sound?

line conditioner or iso transformer help with RFI or they only good to clean up power?

i have all ungrounded cdp , pre and amp. would shielding PC help with floating ground units to reduce RFI?

my system:
cdp cyrus 8x with psr (no ground from unit)
pre amc cvt 1030 (no ground from unit)
amp amc cvt 2100 (no ground from unit)
cd buffer yaqin 6j1
belden diy PC
lessloss PC
few diy shielded and unshielded PC
audio art ic-3
gabriel gold Rev
kci silkworm
xindak fs gold
spendor s 3/5
porter port outlet on the way

thanks in advance