Bluetooth sent from Iphone SE is always mono. Can this be fixed?

Rather than edit my post, I'd like to explain that I was partially wrong and offer some advise. The problem was two-fold. First and most important, a great deal of low cost Bluetooth receiver modules falsely advertise themselves as stereo, but absolutely are not! I have verified this by dissembling them and tracing their internal PC board connections, and in several of them the left and right outputs are physically connected together! Unbelievably obvious fraud! Second, there was at least one I found made for DIY folks (3rd one in photo) whose internal wiring seemed like it really should be producing stereo. (The left and right were physically connected to separate coupling capacitors and different output pins on the Bluetooth IC). In that case I believe the problem is that the Bluetooth chip itself is simply not compatible with the I phone. It will work, but both channels will be identical (mono).

But anyway, in the end I found that the I phone can indeed work as a true stereo Bluetooth transmitter with the right adapters. I was looking for DIY solutions and was finally able to find a bare board that worked well (true stereo) and allowed me to build several small adapters for my vehicles as well as various household sound systems that had AUX inputs. I also found at least one "off the shelf" brand of adapter non DIY folks made by a company called "ByDiffer", that also did true stereo and does not require soldering or work with bare circuit boards.

So my recommendation is to save yourself some frustration and wasted time by buying Bluetooth adapters from a reputable business where you can easily return the product easily if its not compatible. I'm also going to post a graphic showing 4 low cost adapters that despite all appearances and advertising will NOT produce stereo sound with your Iphone. For the DIY'ers, I'll also post a picture of the bare board I had most success with. Those are pretty easy to find online in places like ebay and such (No, I don't currently sell them). I like those because I can easily supply external power (they need 5VDC), they don't make a stupid verbal announcement (like "NOW CONNECTED") when pairing, and once paired the first time, they will auto connect whenever power is applied ( no need to press a "pair" button.) I will just warn that those boards are very small, and require skill and a fine pointed soldering iron to work with.

Anyway, hopefully I've helped clear up some of the reasons this problem happens to so many, and maybe helped some DIY folks find something they can rely on.

These DIY boards definitely work well. They are all over ebay and similar outlets too. (No, I don't currently sell them!)

I have tried sending my Iphone audio through multiple bluetooth receiver adapters, hoping to be able to listen through my car's audio system. Anything played through the bluetooth link comes out mono (not stereo). It is easy to hear and easily proved using one of the many I stereo test videos on youtube. I know there are some bogus adapters out there, but this one has been verified using a friend's android phone, so the problem is the Iphone. I have verified that the "mono only" setting in the phone's accessibility is not turned on. I've also verified that it only affects earbuds plugged in through a lightning-to-headphone adapter. I haven't upgraded to the latest IOS 17.1.2 yet, but this problem has persisted through several IOS updates (I'm at IOS 16.x now.... please ignore the automatic incorrect words about Iphone 5, IOS 12 added by the system). I also have discovered this same complaint mentioned many times on this forum and others, and the solutions mentioned (power down then up, IOS upgrade, check mono only setting) don't work. I'm about to buy a separate bluetooth transmitter to plug into the lightning port through the headphone adapter, since I know that output is definitely stereo. So other than waiting for apple to someday fix their bluetooth transmission, does anyone know of a trick that works? If so, please test your solution using sound who's stereo effect is easily recognized (or one of those youtube stereo test videos). Thanks for any help.