  We use the Random Matrix Theory (RMT) to study the probability distribution
function and moments of the wave power transmitted inside systems with ergodic
wave motion. The results describe either open multichannel systems or their
closed counterparts with local-in-space internal dissipation. We concentrate on
the regime of broken time-reversal invariance and employ two different
analytical approaches: the exact supersymmetry method and a simpler technique
that uses RMT eigenstatistics for closed non-dissipative systems as an input.
The results of the supersymmetric method were confirmed by numerical
simulation. The simpler method is found to be adequate for closed systems with
uniform dissipation, or in the limit of a large number of weak local dampers.
