diff --git a/R/geneView.R b/R/geneView.R
index 55f64c0..6061fdc 100644
--- a/R/geneView.R
+++ b/R/geneView.R
@@ -306,7 +306,7 @@ geneView <- function(input, output, session, data, metadata, level = NULL, plot.
 
   #enable plot button only if plot possible
   shiny::observe({
-    if(is.null(input$genes) | length(selector$selectedColumns()) < 1){
+    if(is.null(input$genes) || !shiny::isTruthy(selector$selectedColumns())){
       shinyjs::disable("plot")
     }else if(input$plotType == "violin"){
       factor1.levels <- metadata.r()[level == selector$type() & key %in% selector$selectedColumns() & factor1 != ""][, .N, keyby = factor1][["N"]]
diff --git a/R/pca.R b/R/pca.R
index 249af4f..8d4d166 100644
--- a/R/pca.R
+++ b/R/pca.R
@@ -111,7 +111,7 @@ pca <- function(input, output, session, data, types, levels = NULL, entryLabel =
   })
   levels.r <- shiny::reactive({
     if(is.null(levels)){
-      metadata.r()[["level"]]
+      types.r()[["level"]]
     }else{
       if(shiny::is.reactive(levels)){
         levels()
@@ -162,11 +162,11 @@ pca <- function(input, output, session, data, types, levels = NULL, entryLabel =
     shinyjs::reset("dimB")
     shinyjs::reset("pointsize")
     shinyjs::reset("labelsize")
-    columnSelect <<- shiny::callModule(columnSelector, "select", type.columns = shiny::reactive(types.r()[level %in% levels.r(), c("key", "level"), with = FALSE]), columnTypeLabel = "Column types to choose from")
+    columnSelect <<- shiny::callModule(columnSelector, "select", type.columns = shiny::reactive(types.r()[level %in% levels.r()]), columnTypeLabel = "Column types to choose from")
     clearPlot(TRUE)
   })
 
-  columnSelect <- shiny::callModule(columnSelector, "select", type.columns = shiny::reactive(types.r()[level %in% levels.r(), c("key", "level"), with = FALSE]), columnTypeLabel = "Column types to choose from")
+  columnSelect <- shiny::callModule(columnSelector, "select", type.columns = shiny::reactive(types.r()[level %in% levels.r()]), columnTypeLabel = "Column types to choose from")
 
   output$datalevel <- shiny::renderUI({
     shiny::selectInput(session$ns("select"), label = "select data level", choices = unique(levels.r()))