changing decay lenght in grid edit during editing

my program is in "mono"- and "oneshot"- mode. all samples should play until the next trigger signal is recorded. with "mode" + "pad 15" i open the "grid edit". if i hit the sample pads and move to "step edit" all pads have the same decay value. i changed the value manually. how can change the decay lenght of all samples in "grid edit"-mode?

thanks in advance

any hint is welcome.

If those are oneshots, you don't need to set a duration (D is for duration here), as they will last no matter what the value is. I use Seq Edit if there's need for that one, and it's used for "note on".