難点なんてん
nanten

Noun

1. fault; weakness; flaw; defect; drawback; disadvantage

あそこのものはうまいし値段ねだんやすいが、地わるいのが難点なんてんだね。
asokono tabemonowa umaishi nedammo yasuiga chinoriga warui noga nantendane.
That place's food is great, and their prices are good, but the fly in the ointment is their terrible location.
Noun

2. crux (of a matter); difficult point; point of contention

ただし瞬間しゅんかん気圧きあつ変化へんかのせいでしょうか、耳みみがツンとするのが難点なんてんです。
tadashi oshikomu shunkan kiatsuno henkano seideshōka mimiga tsunto suru noga nantendesu.
However, maybe from the sudden change in pressure when you push them in, having your ears pop is a problem.