hello spit,
path balance is entirely due to a faulty hardware, it shows a higher loss in the BTS’s reception path, or on the opposite, a higher loss in the BTS’s transmission path.
Depending on your formula :
path bal > +5dB : problem in the Tx
path bal < -5dB : problem in the Rx
Most common problems are : faulty TRX or faulty combiner
Other possible problems :
faulty feeders, connectors, jumpers, antennas
And finally, it might also help you find out crossed feeders (Rx on one sector, and Tx on another sector)