diff --git a/internal/bundb/group.go b/internal/bundb/group.go
index 3d5df3a..4b68665 100644
--- a/internal/bundb/group.go
+++ b/internal/bundb/group.go
@@ -90,11 +90,19 @@ type updateGroupsParamsApplier struct {
 
 func (u updateGroupsParamsApplier) apply(q *bun.UpdateQuery) *bun.UpdateQuery {
 	if u.params.ChannelGains.Valid {
-		q = q.Set("channel_gains = ?", u.params.ChannelGains.String)
+		if u.params.ChannelGains.String != "" {
+			q = q.Set("channel_gains = ?", u.params.ChannelGains.String)
+		} else {
+			q = q.Set("channel_gains = NULL")
+		}
 	}
 
 	if u.params.ChannelLosses.Valid {
-		q = q.Set("channel_losses = ?", u.params.ChannelLosses.String)
+		if u.params.ChannelLosses.String != "" {
+			q = q.Set("channel_losses = ?", u.params.ChannelLosses.String)
+		} else {
+			q = q.Set("channel_losses = NULL")
+		}
 	}
 
 	if u.params.ServerKey.Valid {