My digital cable box has just one digital (coaxial) output. When connecting a splitter to feed the 5.1 signal to both my HT systems audio was fine on one receiver but did not come through on the other (even though it indicated receiving a digital signal). When the coaxial was connected directly to the receiver audio was OK so it was not due to the 75 ohm cables I used. Is there a proper way to split a 5.1 signal from a coaxial output? Unfortunately, the only digital splitters available are optical (and my brother encountered a distorted signal on one source when using an optical splitter for audio recording). Any help would be appreciated.