K8098 audio analyzer screen goes mad

Hi, I’m having a problem with the screen of the K8098 kit. It works fine for about half an hour, then the screen gets scrambled and is unreadable.
What could be the problem?

Difficult to tell without being able to examine your circuit.
If the problem is not caused by a mechanical issue (loose or bad soldering, loose track or pad, thermal issie, bad contact, etc…), then we suggest to return the kit for inspection/repair.

I could not find any loose soldering. Temperature seems normal. How can I return the kit for repair?

Please return it to your distributor or direct to Velleman:

Velleman Projects Tech. Dept.
Legen Heirweg 33
9890 Gavere

US residents: please call (817) 284 77 85 for RMA#

Please include a detailed fault description.