Felt I tuned it badly (8)
I believe the answer is:
intuited
'felt' is the definition.
The definition and answer can be both related to thinking as well as being past participle verbs.
Perhaps they are linked in a way I don't understand?
'i tuned it badly' is the wordplay.
'badly' is an anagram indicator (letters in the wrong order).
'tuned'+'it'='tunedit'
'tunedit' is an anagram of 'ntuited'.
'i'+'ntuited'='INTUITED'
Can you help me to learn more?
(Another definition for intuited that I've seen is " Instinctively knew".)