hi nsnopti,
do you reckon it could be a problem of feeder swap ? the bcch might be always located on the same feeder, due to combiner choice, that’s why you always see it with a low rxlev, whichever the physical TRX.
otherwise, you should try to delete the cell from OMC-R (or even the whole BTS), and re-create it from scratch (that’s an old ALU trick…)
if nothing works, then assume the hardware is faulty (probably your combiner(s))
regards
pix