I am on a Kickr Snap and using IOS with Bluetooth so it does not pick up my speed and cadence which is on ANT+. When I am riding in a group and it is holding my watts nothing I do will accelerate me. If I push harder in erg mode is adjust my target wattage to what I am supposed to be doing which means if I accelerate to chase another rider down my character does not increase his speed.
Second issue is that if I push a bigger gear and get the flywheel spinning fast when I back off even a little so that I am not pushing the flywheel faster then it drops my speed to next to nothing until the flywheel slows down so that I can start pushing it again. Is this a set up issue or just the nature of the system.