Only the A2DP profile is used.
SPDiF signal from the BC127 HD Module enters Digital Interface Receiver IC and then I2S into digital amplifier.
When a music on the phone begins to play or audio stream starts, it is noticeable that the sound level ramps up slowly.
In some situation, that is too slow to enjoy music. For example, Billy Joel’s ‘Piano man’ starts with strong attack of piano but the sound via BC127 HD makes the attack too weak.
The attached photo shows the sound level ramp up observed at the amplifier output.
Ch.1 is SPDiF out from the BC127 HD and Ch.2 is the amplifier output.
(Time division is 200ms)
It takes about more than 800ms to reach 90% level of normal level after the SPDiF begins to stream.
800ms is enough time to miss one or two beats in Moderato.
I tried to configure BC127 HD to reduce the ramp up time(or soft mute release time) but cannot find out in User’s Guide. There is a possibility that the too slow ramp is from the phone or others but BC127 HD is most suspicious by many experiments.
Is there anyone who knows how to fix this problem or suffers the same?
Thanks for all.
p. s. Here are some configurations related.
Melody Audio V7.1 HD
AUDIO_DIGITAL=2 44100 64 9 ON
PROFILES=0 0 1 0 0 0 0 0 0 0 0 0