It sounds like the main figure is not selected before creating the clothing item (with the Figure 1 and Body:1 version). This will cause the clothing item to follow the morphs in whatever figure was selected when you created the clothes... instead of Figure 1.

For clothing items to work properly in Daz Studio you need the PBM in front of the dials that correspond with the figure morphs.

targetGeom PBMMuscular1
{
.
.
.
valueOpDeltaAdd
Figure 1
BODY:1
PBMMuscular1

Mada

...faith, trust and pixiedust