Tuning issues are usually caused by a bad U264B chip (IC8-Board2) or a broken wire on the coax cable between the FM board and the CPU board. Replacement U264B chips can be hit or miss for working with a BM6000 (depending on the manufacturer). The ones sold at beoparts-shop.com work well. The cheap ones from China sometimes work, but you might need to try a handful of them before you find one that is compatible. The broken coax wire is usually at the CPU end of the cable where the center wire connects to the connector pin. This can be repaired by soldering in a short piece of wire to reestablish the connection. Glitch  

I just checked, all the cable connections are fine, and there are no issues there. I believe the problem lies with the IC (Integrated Circuit). I am contemplating whether to get the IC from China, which may offer faster delivery, but the quality might be inferior.

Hi, The prescaler chip, yes, a no brainer. A classic failure: many of us have had this fault. Beware there are fakes around, especially from Asia. Here for the real deal: https://www.beoparts-shop.com/product/prescaler-ic-u264b-for-beomaster-6000-8000