TableView lag when scrolling - ios

Question

When you scroll through the table appear lags. Pictures, or long texts in the database do not. Sorry, for my bad English
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
var cell = tableView.dequeueReusableCellWithIdentifier("audioCell", forIndexPath: indexPath) as? AudiosTableViewCell
if cell == nil {
cell = UITableViewCell(style: UITableViewCellStyle.Value1, reuseIdentifier: "audioCell") as? AudiosTableViewCell
} else {
let realm = try! Realm()
let audios = realm.objects(Music)[indexPath.row]
let duration = audios.duration
var durationString = ""
if duration/60 < 10 {
durationString = durationString + "0" }
durationString = durationString + String(duration/60) + ":"
if duration%60 < 10 {
durationString = durationString + "0" }
durationString = durationString + String(duration%60)
cell!.artistLabel.text = audios.artist
cell!.titleLabel.text = audios.title
cell!.durationLabel.text = durationString
}
return cell!
}
If you need additional information, write exactly what you need. I've reviewed a lot of information, tried many methods, the third day I am suffering, it does not work

Answer 1

This
let realm = try! Realm()
should be done on videoDidLoad or similar but only once I suggest
if audios.count == 0 {
let realm = try! Realm()
let audios = realm.objects(Music)[indexPath.row]
}
then replace
let realm = try! Realm()
let audiosStore = realm.objects(Music)
with
let audios = audiosStore[indexPath.row]
When you call
let realm = try! Realm()
You are asking for all the objects from Realm each time.

Answer 2

Can you move this code to out of cellForRow, and be sure call it before cellForRow triggers.
let realm = try! Realm()

Answer 3

tableView.dequeueReusableCellWithIdentifier("audioCell", forIndexPath: indexPath) never returns nil. If you already know cell will have class AudiosTableViewCell you can rewrite code as follows:
// Make realm property of your view controller
let realm: Realm!
// In viewDidLoad
realm = try! Realm()
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("audioCell", forIndexPath: indexPath) as! AudiosTableViewCell
let audios = realm.objects(Music)[indexPath.row]
let duration = audios.duration
var durationString = ""
if duration/60 < 10 {
durationString = durationString + "0" }
durationString = durationString + String(duration/60) + ":"
if duration%60 < 10 {
durationString = durationString + "0" }
durationString = durationString + String(duration%60)
cell.artistLabel.text = audios.artist
cell.titleLabel.text = audios.title
cell.durationLabel.text = durationString
return cell
}