On the bottom string I get a strange twangy sound when using my index finger but if I use my thumb it sounds fine , is it a technique issue or does my finger need softening or something.
It's probably a technique thing resulting from pulling up on or tearing at the string. Focus on displacing the string toward the soundboard/fretboard plane. If it helps, imagine yourself pushing through the string and focus on how the finger addresses, applies pressure to, and releases the string.
It's probably a technique thing resulting from pulling up on or tearing at the string. Focus on displacing the string toward the soundboard/fretboard plane. If it helps, imagine yourself pushing through the string and focus on how the finger addresses, applies pressure to, and releases the string.