I am using H9 Control version 4.0.1 on a Mac running macOS Catalina (10.15.7).
The problem I am having is connecting to them from the Mac using Bluetooth. I have previously been able to connect to both simultaneously, but now it seems that I can only connect to one at a time.
After connecting to one, I choose Devices -> Connect Device via Bluetooth and I am presented the Bluetooth screen that lists both pedals. The one already connected shows “Connected” and the one I want to connect to shows “Not connected”. I double-click on the one that is “Not Connected” and it connects and the Bluetooth dialog closes. Then the connection to the device I already had connected with is closed (shows “Not Connected” in Bluetooth dialog). Then, in H9 Control, it immediately shows the “Device not found! dialog. However, at the top of the screen, I see the one I just connected to being shown as connected.
In order to control this one, I then have to choose “Use app in demo mode”, Then, H9 Control goes back to normal and I can control the H9 I just connected to….
Device -> Connect Device via Bluetooth
Double click H9-B in Bluetooth dialog
H9-B connected, H9-A disconnected, Bluetooth dialog closes