GW-M5610 (3159) gaining +30s/day, no sync

Hi everyone, I’m looking for some technical advice on my GW-M5610 (Module 3159), purchased in June 2021. Since October, the watch has stopped syncing via Multi Band 6 (I’m located in Vienna, Austria, where reception is usually excellent). Simultaneously, the accuracy took a massive hit. It is currently gaining +30 seconds per day.

No physical trauma: The watch hasn't been dropped or hit against anything. It’s in great physical shape.

Battery: Currently on "H" (High).

AC Reset: I performed a manual AC reset. The watch went into "CHG" mode briefly but recovered quickly. However, the time gain persists.

Sync Issues: Manual sync fails every time. I also tried using DCF77 emulator apps to sync via the phone's speaker, but the watch doesn't pick up the signal at all.

It seems like the quartz oscillator or the receiving circuit has developed a serious fault. Since it's gaining half a minute every day, it's becoming pretty much useless as a precision timepiece. Is there any known fix for a "galloping" module like this, or is the 3159 simply reaching the end of its life? Should I consider a module swap or just upgrade to the new GW-BX5600? Thanks for your help!