IOS: Bluetooth not auto connecting to previously paired device

Neither my iPhone nor iPad can auto connect (auto-pair) to a bluetooth audio device. However it works on Android and OSX Yosemite.

I have a bluetooth stereo system receiver: beewi bbr100. http://ift.tt/1vbsrqM

Steps on iPhone/iPad are: 1. Turn on Bluetooth 2. Select and pair beewi bbr100 device (unknown until now) 3. Works fine 4. Turn off Bluetooth 5. Turn on Bluetooth 6. Does not automatically pair it. (I expect it to. Android and OSX work fine)

Summary of my testing: iPad OSX 8.1.2 - No iPhone OSX 7.0.5 - No Android (Lollipop) - Yes Macbook Air (OSX Yosemite) - Yes

I did go through the Apple troubleshooting guide. Yes I did reset network settings. Yes I did log out of icloud. Yes I did do a Hard reboot.

Is there something I don't understand?