problems with braille sense OnHand as a braille display for IPhone 6

Does anyone have any tips for getting a braillesense OnHand to work better with my IPHone 6? I have paired it and it is showing braille but when I am trying to scroll the display with the scrolling buttons, I have to press them several times in order for the display to actually scroll. Similarly when I am typing letters, I have to press a letter several times for it to show up. I have 8-dot braille set in voiceover settings for both input and output. anything else I am missing? Specifically I am trying to read braille books using the bard mobile app so I need to be able to scroll the display quickly. Thanks for any help!