So I just upgraded from an Alpine CDA-9883 to an HD-149BT and now the mute button on my dash no longer functions. I *think* the CH button is also malfunctioning in iPod mode but I need to do further testing to be sure. At any rate, I'm wondering whether this problem is because I have an older wired DCI. The original owner had the DCI installed back when the car was new (2004). Here's a picture of the DCI I have.



Any suggestions?

 

ok, this is kind of a longshot, but I'll take a crack at it...
The DCI can send a mute command two ways - through the regular wire as a remote command, like you
pressed the "mute" button on a remote, or through a dedicated Tel/Mute wire which was used to
automatically mute the headunit when a hardwired cell phone rang. The latter is probably never
used in the modern Bluetooth era, and it wouldn't surprise me if the new headunit doesn't support
it. If the old headunit did, and the DCI was set up that way, the mute would no longer work.
Fortunately the DCI is switchable between the two methods with one of those dipswitches, but you
may need to track down old documentation to figure out which one.