Music is the voice of shaytaan

It is prohibited to occupy oneself with playing music or listening to it whether accompanied by singing or not. Singing is Haram (prohibited).

It falls under vain talk. Songs, music, and all forms of vain amusement damage the Muslim's heart, lead to evil, and distract them from good deeds. It seduces people to commit evil and neglect their religious duties. It leads to distraction, Fitnah (temptation) and corruption. Listening to vain amusement and musical instruments is unanimously Haram (prohibited) as stated by many scholars.The prohibition becomes all the more empathic if it is accompanied by singing as it ruins morals and corrupts true belief.It is also impermissible to teach or learn music. Listening to songs entails being inclined to them.The type of songs which people hear on TV or listen to on the radio, falls under the category of Haram because it is diversion which stimulates sexual desire and arouses passion. These songs also lead to moral decline, sickening of the soul that divert it from performing noble deeds. They also help in the quick spread of corruption in Islamic environments.

Allah (Exalted be He) says in Soorah Luqmaan (31) - Aayah 6 -7:

وَمِنَ النَّاسِ مَن يَشْتَرِي لَهْوَ الْحَدِيثِ لِيُضِلَّ عَن سَبِيلِ اللَّـهِ بِغَيْرِ عِلْمٍ وَيَتَّخِذَهَا هُزُوًا ۚ أُولَـٰئِكَ لَهُمْ عَذَابٌ مُّهِينٌ ﴿٦﴾ وَإِذَا تُتْلَىٰ عَلَيْهِ آيَاتُنَا وَلَّىٰ مُسْتَكْبِرًا كَأَن لَّمْ يَسْمَعْهَا كَأَنَّ فِي أُذُنَيْهِ وَقْرًا ۖ فَبَشِّرْهُ بِعَذَابٍ أَلِيمٍ

And of mankind is he who purchases idle talks (i.e. music, singing, etc.) to mislead (men) from the Path of Allâh without knowledge, and takes it (the Path of Allâh, or the Verses of the Qur’ân) by way of mockery. For such there will be a humiliating torment (in the Hell-fire). And when Our Verses (of the Qur’ân) are recited to such a one, he turns away in pride, as if he heard them not - as if there were deafness in his ear. So announce to him a painful torment.

The "idle talk" mentioned here, refers to singing, as interpreted by a number of the Sahabah (Companions of the Prophet). `Abdullah ibn Mas`ud said: "It is singing, by Allah Who is the Only One worthy of worship." He repeated it three times.
According to the majority of Mufassirs (exegete of the Qur'an), the 'idle talks' refers to singing and sounds of musical instruments.
Regarding the Saying of Allaah:
And of mankind is he who purchases idle talks (i.e. music, singing, etc.) to mislead (men) from the Path of Allâh without knowledge
Qatadah said:

"By Allah, it may not mean spending money to purchase it, but purchasing here means preferring it. It is sufficient to be considered an act of misguidance that a person
prefers false speech to true speech, and what brings about harm to what brings about benefit."

It is, thus, Fitnah (temptation) to the heart that attracts it to evil and distracts it from good. Even more, it wastes time idly and, thus, falls under the purport of "idle talk".
Anyone who sings or listens to such songs is classified among those who purchase idle talk to distract themselves or others from the Path of Allah. Allah has dispraised this act and threatened the doers with humiliating torture.

It is not permissible for a Muslim to work as a musician and the earnings he gets from that are Haram (prohibited); It is not permissible for someone to record songs and music, or the like, on audio cassette tapes nor sell or purchase them even if you do not listen to them. This work is considered cooperation in sin and transgression with the people who will use these tapes according to the Statement of Allah (Praised and Exalted be He) says in soorah Al Maa'idah (5) - (part of) Aayah 2:

وَتَعَاوَنُوا عَلَى الْبِرِّ وَالتَّقْوَىٰ ۖ وَلَا تَعَاوَنُوا عَلَى الْإِثْمِ وَالْعُدْوَانِ
Help you one another in Al-Birr and At-Taqwâ (virtue, righteousness and piety); but do not help one another in sin and transgression.

Also, Allah (Exalted be He) addresses Satan in soorah al Israa'(17) Aayah 64, saying,

وَاسْتَفْزِزْ مَنِ اسْتَطَعْتَ مِنْهُم بِصَوْتِكَ

And befool them gradually those whom you can among them with your voice
(i.e. songs, music, and any other call for Allâh’s disobedience)

The Companions of the Prophet (peace be upon him) also interpreted shaytaan's voice to include singing and pipes.
In this regard, we recommend the book titled "Ighathat Al-Lahfan" by Ibn Al-Qayyim who discussed this point in detail.

Singing and musical instruments result in hardness and disease of the heart and turns it away from listening to the Ever-Glorious Qur'an and useful sciences.
Undoubtedly, this is one of the tricks of Shaytaan by which he tries to deceive the people who lack knowledge and religion, so that they prefer listening to the recitations of Satan – namely songs – to listening to the Book of Allah and the Hadiths of His Messenger (peace be upon him).
The Salaf rebuked severely those who occupied themselves with singing and musical instruments, described them with insolence and Fisq (flagrant violation of Islamic law)

An even graver prohibition is that people recite the Qur'an in a musical tone. This is a desecration of the Qur'an, and associates it with songs chanted for entertainment. Also making supplications accompanied by music is mockery and mixing `Ibadah (worship) with amusement. If the supplications are tinged with Bid`ah (innovation in religion), this is even worse
Moreover, it involves imitating the customs of non-Muslims.

It is related in "Sahih" Book of authentic Hadith by Al-Bukhari that the Messenger of Allah (peace be upon him) said,

''At the end of time, there will be some people who will consider illegal sexual intercourse, the wearing of silk (for men), the drinking of Khamr (intoxicant) and the use of musical instruments as lawful. Allah will make the earth sink with them''

Preoccupation with singing and musical instruments leads to weakness of Iman (belief) and lack of shyness and piety.
Even more, it results in belittling the Commands and Prohibitions of Allaah. The people preoccupied with singing and musical instruments become in a state of heedlessness, recline to falsehood, become sluggish to perform Salah (Prayer) and acts of charity, but active in doing evils which signing drives to.
It is also not permissible to use music as a 'cure' for illnesses. A Muslim is not in need of such cure; especially when there exists other lawful substitutes like recitation of the Qur'an.
Using singing as a means for 'Dawah' is invented by misguided Sufis and not by the followers of Sunnah. Singing is Haram and it is not permissible to make Da`wah depending on a prohibited means.

`Abdullah ibn Mas`ud (may Allah be pleased with him) said:

"Songs plant hypocrisy in
the heart as water plants legumes."

It is related by Ahmad in his Musnad through a good Sanad (chain of narrators) on the authority of Ibn `Abbas (may Allah be pleased with him and his father) that the Prophet (peace be upon him) said:

''Allah has forbidden Khamr, gambling, Kubah (drums), and every intoxicant.''
The Kubah is the drum as mentioned by Sufyan, a narrator of the Hadith.
Songs and musical instruments are considered some of the most abominable idle talk that turns people away from the Qur'an and the Way of Allah. Singing is the recitation of Shaytaan and an evil that leads to Zina (sexual intercourse outside marriage), homosexuality, and all kinds of malicious acts and vices.
Shaytaan uses singing to make people abandon the Qur'an and be vulnerable to committing sins of homosexuality and Zina (sexual intercourse outside marriage). It is the way for seduction and temptation, as Satan beautifies it in the eyes of the ignorant and makes them inclined to hear it more and more. Their hearts are spoiled and thus they become heedless of the Qur'an.

It is also related by Al-Tirmidhy on the authority of `Imran ibn Al-Husayn (may Allah be merciful to him) that the Messenger of Allah (peace be upon him) said:

'There will be stoning, earth's swallowing up, and distortion in my people.' A Muslim man asked, 'When will that happen, O Messenger of Allah?' He (peace be upon him) replied, 'When female singers and musical instruments spread and Khamr is drunk.'