Fast Battery Drain Even With New Battery

[ih8apl]

I did not see a thread on this so I registered so that I could post this problem. I have an EVO 4G that I purchased used. I only want to use it as an MP3 player. As such, I put it in airplane mode. After 45 minutes of music playing, the battery would drain down to 15%. I figured this was an old battery and was past its useful life. Therefore, I ordered a new one from Amazon and charged it to 100%. I still have the battery drain problem. Any thoughts?

Thank you

 

[ih8apl]

I can tell by the lack of responses that this is unsolvable. By the way, never buy a phone from thebluedot.net they sold me this non-working phone, wouldn't refund my money, got the listing deleted from Ebay so I couldn't leave feedback and now I have no record that I purchased the phone. Ebay is letting sellers run all over buyers in an attempt to compete with Amazon. I'm pretty much stuck with a non-mobile mobile phone.