This question has been answere here before; but it is confusing...so here we go....
Complete the analog connections between the BV-5 and the BL-5's as normal. Complete the S/PDIF daisychain from the BR-2 socket box to the BL-5's as described earlier here. As you point out, there is only one digital output...did you note that there is only one PL output as well? Therein lies the only clue. Run the co-ax from the Socket box to the closest BL-5's S/PDIF input, then note the S/PDIF output on the BL-5; there in lies the 2nd and only other clue. Run coax from that S/PDIF output to the other BL-5. Now, as to the 5.1 signal for DVD's...well...what to do with the S/PDIF output on the 2nd BL-5? Hmmm.
Run a 3rd coax from the un-used S/PDIF output on the 2nd BL-5 to the DVD S/PDIF on the BV-5. IF all of your software is up-to-date, and IF you are using the fully wired PowerLink cables which came with the BL-5's, and IF the L/R switches on the BL-5's are set properly, and IF they're connected to the BV-5 correctly...then when listening to CD's the BL-5's will look for the digital signal on the S/PDIF cables, and when listening to any other source, they will look for the analog signal on the PowerLink cables and ignore the digital stream.
This is accomplished, in part, by using the 'display/data' info on those PowerLink cables which formerly drove the displays on BeoLab Pentas and 4500/5000's to 'tell' the BL-5's what the source is.
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