Soundbox as a Second Screen (SaSS) turns your Qashier Soundbox into a customer-facing payment screen: when you take a QR payment on Qashier POS, the PromptPay QR code appears on the Soundbox so the customer can scan it there. Available in Thailand for PromptPay dynamic QR and manual QR.
Applies to: Thailand · Qashier POS and QashierHQ · Qashier Soundbox · a QashierHQ login with access to Settings.
Before you start
Your Soundbox must first be set up as a QR payment screen by Qashier. This is not something you can switch on yourself. If you do not see QR Payment Screen under Settings > Devices in QashierHQ, contact Qashier Support.
Connect the Soundbox to the internet. See How to connect Qashier Soundbox to WiFi or 4G (SIM card).
Have the Soundbox serial number ready. It is on the label on the back of the device.
Set up the Soundbox in QashierHQ
Log in to QashierHQ.
Click the gear icon (Settings) at the top right. On a phone, open your profile menu at the top right and tap Settings.
In the Settings menu on the left, under Devices, click QR Payment Screen.
Choose the store.
In Soundbox Serial Number, enter the serial number of the Soundbox that should display the payment QR codes.
In Terminal Standby Display Line 1, Terminal Standby Display Line 2 and Terminal Standby Display Line 3, type the text shown on the Soundbox while it is idle. Line 1 is required; each line can hold up to 20 characters.
Click Save.
Caution: if your store also lists Soundbox Settings under Devices, do not save changes there for a Soundbox that is used as a QR payment screen. Saving on that page switches the Soundbox back to standard (audio-only) mode.
Take a QR payment with the Soundbox
On Qashier POS, check out as usual and choose the QR payment method: PromptPay dynamic QR, or the manual QR button on the checkout page.
The QR code appears on the Soundbox screen. It is also shown on the POS terminal or tablet.
The customer scans the QR code on the Soundbox and pays.
Confirm the payment:
Dynamic QR: a check mark appears on both the Soundbox and the POS automatically once the payment succeeds, and the POS moves to the payment-received screen.
Manual QR: check the payment confirmation on the customer's phone, then confirm the payment on the POS. The QR code on the Soundbox is dismissed when you confirm or cancel the payment on the POS.
A dynamic QR code generated on the tablet and shown on the Soundbox.
The manual QR button on the POS checkout page.
The customer scans the QR code on the Soundbox.
After a successful payment, the POS moves to the payment-received screen.
What you should see
While idle, the Soundbox shows the standby text you saved in QR Payment Screen.
For each QR checkout, the same QR code appears on the Soundbox and on the POS, and the transaction is recorded in your POS and QashierHQ reports like any other PromptPay payment.
If something goes wrong
Symptom | Likely cause | What to do |
No QR code appears on the Soundbox | The Soundbox is offline, or the serial number saved in QR Payment Screen does not match the device | Check the connection (network guide), then check Soundbox Serial Number in Settings > Devices > QR Payment Screen and click Save |
QR Payment Screen is not listed under Devices | No Soundbox on your account is set up as a QR payment screen yet | Contact support to have it enabled |
The manual QR stays on the Soundbox after the customer paid | The payment has not been confirmed on the POS | Confirm (or cancel) the payment on the POS; this dismisses the QR on the Soundbox |
The Soundbox stopped showing QR codes after you edited Soundbox Settings | Saving there switched the device to standard mode | Contact support to switch it back to QR payment screen mode |
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Last verified: 25 Sep 2026 · Markets: TH