Fixed tone distortion bug after going high

When going higher than chip supports, and when frequency multiplication factor got been increased, it should be properly reset back when going down

Author: Wohlstand

src/adlmidi_opl3.cpp

@@ -523,6 +523,7 @@ void OPL3::noteOn(size_t c1, size_t c2, double tone)
     uint16_t ftone = 0;
     const OplTimbre *patch1 = m_insCache[c1];
     const OplTimbre *patch2 = m_insCache[chan2];
+    bool cacheModded[2] = {m_insCacheModified[c1], m_insCacheModified[chan2]};
 
     if(tone < 0.0)
         tone = 0.0; // Lower than 0 is impossible!
@@ -570,7 +571,7 @@ void OPL3::noteOn(size_t c1, size_t c2, double tone)
                 writeRegI(chip, 0x20 + op_addr[op],  (dt | (mul + mul_offset)) & 0xFF);
                 m_insCacheModified[modIdx] = true;
             }
-            else if(m_insCacheModified[modIdx])
+            else if(cacheModded[op > 1 ? 1 : 0])
             {
                 writeRegI(chip, 0x20 + op_addr[op],  ops[op] & 0xFF);
                 m_insCacheModified[modIdx] = false;