The following is an instruction for writing a small composition:

日本に来て、または外国に行って、次のようなことでカルチャーショックを受けたありますか。
1)　それまで聞いたことがない音を聞いて、びっくりした。
2) 国でよく聞いていた**音がほとんど聞かれないので**、**不思議に思った**。

First, my attempt at translation:

"Have you experienced culture shock from the following things while coming to japan or going to a foreign country?
1) Hearing a sound you haven't heard so far, you were surprised.
2) Because 

...you mostly don't get to hear sounds you often hear in your country...
...sounds which you often heard in your country mostly aren't (to be) heard...

...you think it's strange.
...you think strangely (like "feel" strange?).


So, obviously my problem lies with the two bold parts. 

I think the passive construction could be an indirect passive? I asked about the indirect passive before but I still feel very insecure about it. I also don't know wether I translated it correctly, should it be an indirect passive (version1 of my translation shall represent the case where I assumed that it is an indirect passive.). 


Second, the 不思議に思った gives me a little headache because I'm not sure what effect 不思議に has in this case ^^ It could mean that "I think of something as strange" (which I think is very likely here) or it could mean that "I think strangely", which would be the most direct/closest relation between the adverb and the verb here, but I think it isn't very likely that this is the case here.