The evidences in your possession are not sufficient enough or substantial evidence to prove your allegations of adultery against her. 

In fact you may have to implead the adulterer as a second respondent,  without any evidence you may be able to file a  petition for divorce on the grounds of adultery. 

You cannot file for divorce on grounds of adultery for an incident that happened 8 years back 

2) mere talking for an hour or so during day time does not prove adultery 

3) you can engage detective agency if your wife is having extra marital affair at present 

4) gather evidence then file for divorce 

The proof of adultery is usually indirect and depends largely on circumstantial evidence. This can be established through circumstantial evidence and adultery inferred from such proof. If you are alleging adultery in a matrimonial dispute, the burden is on you to prove it. The standard of proof in proceedings under the Act being initially of a civil nature is by preponderance of, probabilities and not by proving it beyond reasonable doubt. Adulter , as a general rule, is proved by presumptive proof based on:

(i) circumstantial evidence,

(ii) evidence on non-access and the birth of children,

(iii) Contracting venereal disease,

(iv) evidence of visit to houses of ill-repute,

(v) admissions made In previous proceedings,

(vi) confessions and admissions of the parties Mere suspicion is not sufficient.

The evidence you possess is inadequate or insufficient to support your accusations about her adultery. The evidence in hand can be use as a tool at the time of  cross examination of your wife .If she denied its your duty to prove the same 

If you prove in the court that she has performed Adultery then still Adultery reason will be not held for Divorce.

As per Supreme Court Judgement - Adultery will not count for Divorce.

The above evidence will help you in just she has performed Adultery by confessing recording.

Dear Sir,

If such adultery after marriage then you can rely on such recordings and get divorce. However, it is weak point since divorce is made legalized by the Supreme Court. Normally, such evidences which are secret in nature will be accepted even if you have recorded secretly.

- According to Section 13(1) of the Hindu Marriage Act 1955, Any marriage solemnized, whether before or after the commencement of this Act, may on a Petition presented by either the husband or wife, be dissolved by a decree of Divorce on the ground that the other party has, after the solemnization of the marriage, had voluntary sexual intercourse with any person than his or her spouse. 

- In general language we can say that, Adultery is the consensual and voluntary intercourse between a married person with another person, married or unmarried of the opposite sex, and it is a ground for divorce. 

- Further, even a single act of Adultery is sufficient to file a decree of Divorce and this Act is commonly applied on both husband & wife.

- If you having proof with you  that she was indulge in adultery then you can file divorce on this ground , however mere her voice recording is not enough for proving the same before the court , it should supported with other evidence. 

- Further only talking with other unknown person cannot be a ground for divorce , but it can help to show her character. 

Dear Sir,

1. Mere voice recording of your wife without any other supporting evidences is not a solid ground for divorce.

2. Also call records won't prove your allegation, it requires supporting and coroborative evidence

3. You have to prove the unchastity of your wife before the court and also have to implead the adulterer as a party before the court

Thank You

Her secretly recorded video would not alone suffice to prove adultery but it can be used to prove cruelty which is also a valid ground for divorce under Hindu Marriage Act 

Dear Querist, in relation to your query my opinion is:-

1. Adultery is no more a crime in India so it can help you only to take divorce on this ground.

2. Yes, it can be useful in your case for divorce unless she refuses to admit her own statement, in that case you have to prove it to be true.

3. No evidence which is presented before court is admissible unless it is proved, so you have to prove it. 

4. For call recording as well, you have to prove the veracity of this evidence in the court.

Please feel free to call.

Hi,  video recording will not help your case.  But you can file a petition for divorce on the ground of Adultery.

Yes you need to prove the same through electronic evidence under 65b of evidence Act. If you need any further assistance then you can approach me through LinkedIn.