( ( Among ( ( the ( most ( frequent complaints ) ) ) ( voiced ( by hearing ) ) ) ) ( ( aid users ) ( ( are ( ( ( that ( noise ( is ( amplified ( too much ) ) ) ) ) and ) ( that ( ( certain sounds ) ( become ( too ( loud ( for ( the ( user ( to bear ) ) ) ) ) ) ) ) ) ) ) . ) ) )
(ROOT (S (PP (IN Among) (NP (NP (DT the) (RBS most) (JJ frequent) (NNS complaints)) (VP (VBN voiced) (PP (IN by) (NP (NN hearing)))))) (NP (NN aid) (NNS users)) (VP (VBP are) (SBAR (SBAR (IN that) (S (NP (NN noise)) (VP (VBZ is) (VP (VBN amplified) (ADVP (RB too) (RB much)))))) (CC and) (SBAR (IN that) (S (NP (JJ certain) (NNS sounds)) (VP (VBP become) (ADJP (RB too) (JJ loud) (PP (IN for) (NP (DT the) (NN user) (S (VP (TO to) (VP (VB bear)))))))))))) (. .)))
Among the most frequent complaints voiced by hearing aid users are that noise is amplified too much and  that certain sounds become too loud for the user to bear.
(ROOT (S (S (VP (VBN Amplified))) (, ,) (NP (PRP it)) (VP (VBZ becomes) (SBAR (S (NP (NNP louder)) (VP (VBZ happens) (VP (VB do) (NP (DT the) (NN sound)) (PP (IN during) (NP (DT a) (NN resonance)))))))) (. .)))