Batboard

I have an UHF Astro Saber III (450-512 MHz). The radio works great except for one problem. When I am listening to channels (personalities) that are programmed in Astro mode (digital) and at 2.5 Khz spacing, there is a machine gun stutter like problem in the audio. It sounds like the dispatcher or field unit audio locks up during the transmissions. I do not have the problem with any of the channels (personalities) that are in non-Astro modes (analog). I also have an Astro Saber II programmed identical to the AS III, but the AS II does not have the same problem with the audio. Does anyone have any ideas what might be causing this? Any information would be greatly appreciated.

Thanks, Badboys