Alpine handsfree problem

[Jimmytno1]

Hopefully this is in the right place and someone can help, I've got an alpine cdt-114bti head unit which I have used in 3 or 4 different cars before with no issues, but after recently installing it into a Mercedes A class (I know, hairdressers car)! I am having trouble with the hands free microphone. I can make and recieve calls using the Bluetooth on the headset with my iPhone but the microphone doesn't work so the person on the other end can't hear me. I thought maybe I damaged the cable whilst fitting it so I ordered a replacement which hasn't made any odds. Everything else works fine and I have also tried resetting my phone and clearing paired devices from the head unit and then pairing up again but to no avail. Any help would be much appreciated
Jimmy

[Jimmytno1]

Bump! It really annoys me when something doesn't work properly!

[GoneAnon]

Have you perhaps altered a setting like mic level or even call mute?

Check the manual for the correct menu to look at these settings and/or their default settings.

[Jimmytno1]

I've checked the settings which all seem to be ok, I'm gonna have another look through the manual and make sure I've not missed anything, thank you for the reply!

[GoneAnon]

Do you have an old cassette recorder or something with a mic socket so you can try the mic and see if that works ok?

[Jimmytno1]

I've not done that yet, I've tried a brand new microphone which still didn't work so I'm pretty sure (unless I've been sent a duff new one) there is a mute setting somewhere I've managed to enable. I was gonna go out to the car tonight and have another fiddle but its cold out and I've got some guiness in the fridge calling my name!

[Boggie]

Hi Jimmy,

Did you find out what this was please? I have exactly the same issue with my Alpine 113BT. I have tried three different mics and even stripped the unit down to check for dry joints on the PCB but nothing apoears to be wromg with the unit. Three evenings so far wasted so I would really aporeciate any help and advice.

Cheers,
B

[Jimmytno1]

Hi, I had the head unit checked over by a local car audio specialist and the first thing they did was try a genuine Alpine microphone and it worked straight away! Still working now in fact, just in a different car. From memory the genuine one cost me about £12.
Hope this helps
Jimmy

[Boggie]

Thanks Jimmy,

Ordered! I will let you know....

[Boggie]

Update: new genuine Alpine microphone sorted this but by comparing it to an after-market mic I now know the difference: Alpine use a standard stereo 3.5mm jack but connect the mic signal to the end and middle pins. A standard three pin mic plug is either stereo L/R hot signal on these pins or mono on both and the upper (closest to the plug wire) carries the common cold/shield.

So, to convert a standard 3-pin jack you need to swap the upper and centre but leave the end pin as it us. A simple bit of soldering on a jack and socket for a couple of quid is better than the £35 Alpine want for a replacement.

Thanks for the pointer!