Hello Marshall Team,
i figured out following:
If code25 is in pairing mode (pressing REV/POWER), you can see that code25 sends a device name ( something like "CODE V02004FA6E") within BT message to phone and phone asks for pairing, all works ok.
after switching power off and on again on code25, code25 sends again BT message but without device name, I guess the phone can't compare the device and thats why the paired connection can't be re-established from phone.
I checked this with BluetoothView v1.66 from NirSoft with win10.
Is there a way to provide findings to Marshall Software Team?
Not sure if you have checked through the entire Forum but the Bluetooth situation is a common problem across the whole series of CODE amplifiers. Based on my troubleshooting and reading other comments, the problem seems to be with the firmware update. Marshall is well aware of this issue and my understanding is that their development/programming teams are working to correct the issue and release an updated firmware patch. The timing of which has not been determined.
The app on the phone works as intended, at least on Android as I am not an Apple user, and does exactly what it is supposed to do as long as the connection to the amp stays on. The problem is, as you note, the loss of the Bluetooth connection when the amp is switched off. What I can tell you is that I am able to re-establish connectivity and functionality in a matter of a couple of minutes. Sure it would great if I didn't have to but it is not interferring with my use of the equipment.
That's all I got for now. There are numerous work-arounds in the Forum that are similar to yours and I have not seen updates to any posting as yet.
As users, we will need to be patient with Marshall and give them a chance to fix the error.