Bismillahir Rahmaanir Rahim
Wa' lay kum as Salaam wa Rahmatullahi wa Baraakatuhu.
Thank you brother Walid for your very kind comments about the question and answer/ask imam threads. May Allah keep us all in tact, towards what is the truth, and may he prosper our younger generation, with the flourishing knowledge of Islam (amin).
Your first question in relation to music, is that all melodies, that are non-Islamic, for example Bollywood music, soul, hip-hop, reggae, housemusic, should be abstained from. The Messenger of Allah, has clearly told us that these will lead us to the hellfire.
Sometimes, it may be the case, that we enter into an arena, for example work, shop, or supermarket, where we cannot prevent the music from playing. In such a case it is perfectly o.k. to be normal.
Where we listen to the radio, for example, the news or other documentaries, then you do encounter flashes of music, in this case as long as your intention is clear, then there is not a major problem.
The same maybe said for the television, where we watch the news to see what is happening around the world, about the Islamic countries and other civilisations encountered in poverty, then bits of music that are heard should basically be ignored.
The only other types of melodies that can be thought of are the na'at, which is a Sunnah of the Messenger of Allah (peace be upon Him), qiraa'ah, which is fard, qawwaali, which gives spiritual closeness from the words that are listened to, in order to unite with the beloved (i.e. Allah the Almighty/Messenger of Allah peace be upon Him), this last form of music, consists of a melodious voice coupled with clapping and drums that are similar to a duff, and the use of a harmonium, that rhymes with the voice of the sayer. This is perfectly normal according the Sufis of the Chishtiyyah Order. However, other Orders may not agree, and because of their disagreement, it may give rise for other sects to claim that it is haraam. This will in effect trigger, the thought of the deviant sects, that will claim that what goes on at the shrines is shirk, which is an absurd and most ignorant way to claim the falsity of a practice, that has remained for centuries, without any hesitation, until these sects had emerged. Then their claims follow from one issue to another, until they claim that the majority of the Muslims in the world are mushrik!
Na a'udhu billahi min dhaalik, may Allah give us refuge from such claims.
Your second question, in relation to weather your hat falls during salaah, is not such a grave issue. It is simple in the sense that one must not try to fumble around, distracting his own salaah, trying to put his hat on, once he is in prostration. This may cause what is known in fiqhi terms as an ''aml-e-kathir', at which your salaah becomes makruh, and near enough disturbed (faasid).
One must always make sure at the beginning of salaah, that all his clothing is fixed properly, including ones topi. Any lose clothing, for example around the neck, or elsewhere can cause the same result.
However, if your topi does fall off, then one should prevent himself from picking it up, as it will cause a niusance, not to oneself, but also to others around him, if he is in congregation (jamaa'ah).
May the Almighty keep us engaged in his dhikr at all times, whether moral, physical, spiritual, or financial.
Wa maa tafiqi illa billahi.
Wallaho a'lamu Biththawaab.
M. Waseem Ashrafi