(With Bose) rear speakers very quiet

[Windymiller]

So last summer I had an ‘issue’ with the stereo system where it just seemed to generate static/white noise at max volume for a couple of minutes until I eventually figured out what was going on, pulled over, turned the car off, got out, locked and unlocked it. Which seemed to sort it. 
 

since then though I just don’t think the sound system has sounded ‘the same’ (especially when I play a known CD). It seems somewhat quieter, and I’ve noticed that I now have to have the sat nav audio at maximum and even then it’s not always audible enough. 
 

the rear speakers (when I put fade all the way to the back) seem very muted. 
 

I previously took her to OPC Silverstone who checked it out. A diagnostic indicated that the Bose ‘amp’ had experienced a ‘short circuit’ (at the time of the loud static) but no fault was there now. They stated the rear speakers were working fine.   But I dont think they are, as they seem too quiet. 
 

just wondering if anyone in Beds (or Cambridge as there quite often too) has a 718 with Bose that I could back to back listen to their and my speakers in with the same audio source?

 

if there is an issue I want to get it sorted under warranty and before this years euro trip in July. 
 

cheers, Jason

[Aaron]

Hey Jason

 

I have the Bose in mine and there are quite a few options that drastically affect the volume output.

 

If you set your audio source and press the physical options button on the headunit, choose "set sound" or something like that.  There's a Bose tab in the bottom of that display with spacious enhancements and some other trickery that affect the output volume quite significantly.

 

The obvious things aside, it might be that the amp has shorted out internally.  It's below one of the seats if you don't mind some effort to get to it and physically inspect the connections!  The amp is probably knackered, based on the white noise output.  That could've killed it, and possibly blown your speakers too.

 

It's a shame you're quite the trip from me as a side-by-side test would be immediately conclusive.  You know where I am if you fancy the drive! 

[Windymiller]

Thanks Aaron, I have had a fiddle with those various settings previously (and has similar ones on my previous 987 PCM with Bose). 
 

I think your point re the amp having ‘shorted’ out (hence now simply not driving the speakers enough) is probably right given that the OPC identified an ‘Amp short cct’ fault code. To my reckoning if something shorts out, it doesn’t then unshort… 🤔🤨

 

I definitely need to make a ‘side by side’ sound check with another 718 with Bose. That will then definitively confirm any difference in output if all other parameters are the same (same source, same ‘song’, same PCM & Bose settings). 
 

Then I can return to OPC (though probably not Silverstone as I am unimpressed with another item of their ‘diagnostics’ previously) and seek to have a new amp (or whatever is required) fitted. 
 

will report back once I’ve found a ‘donor car’ to listen to 😉👍🏻

[Windymiller]

A brief update on this issue.

 

Finally resolved in June by OPC East London (the original supplying dealer) under warranty.

 

Long story short - OPC East LDN diagnosed that the BOSE sub had 'blown' and replaced that.  Now everything sounds like it should.

 

'Well done' to OPC Silverstone for their supposed previous diagnosis - guess where I won't be taking the car for any future servicing nor maintenance....