After a couple of years of NOS service I'd try again the oversampler SAA7030 between the SAA7000 and the TDA1540 dacs. Also I wanted to reclock all the 4 signals before entering DACs: CLCF, L+R, STR1. I used four 74AUC1G74 flip flops and I'm able to reclock L+R and STR1 signal, but CLCF doesn't work: no sound and no signals both on Q and Q/ on scope. Note that flip-flop is ok as it works with another signal. I'm not expert at all on this so.... any suggestion would be appreciated!