If you’ve been experiencing problems using your HTC EVO 4G LTE with the new Airvana AIRAVE 2.5 from Sprint, you’re not alone. Some people are experiencing an issue in which dial tones are being sent to the person on the other end of the call, completely unknown to the person connected to the AIRAVE. In fact, the dial tones become so persistent – and so annoying to the other person – that it becomes almost impossible to carry on a conversation.

This has been happening to me, and it’s gotten so bad that I’ve been forced to unplug the AIRAVE at my house. A quick Google search didn’t turn up much, but I did find at least two other people with the same problem (see here and here). After some experimentation, I was able to narrow it down to a bug with the EVO 4G LTE’s proximity sensor – it seems that whenever the screen turns on or off during a call while the EVO is connected to the AIRAVE, the phone sends some kind of signal that translates into dial tones to the person on the other end of the call. This makes it impossible to navigate through phone trees when calling customer service numbers, and it even impacts my ability to use Google Voice.

I’ve found that using the EVO on speaker or with a headset – in other words, disabling the proximity sensor during the call – will solve the problem. However, I hate using the speaker during calls, and I hate having a headset on all the time, just on the off chance that my phone might ring. In other words, this bug has prevented me from using my EVO with the AIRAVE.

At this time, there seems to be no solution to the problem. Several fixes that I have read about seem to be temporary solutions, with the problem coming back shortly after. According to one person afflicted with the problem, even the highest levels of Sprint tech support have been unable to resolve this, even after “rebuilding” the affected line.

And to be clear, this does not affect other devices connected to the AIRAVE, and it does not affect the EVO when disconnected from the AIRAVE.

My hope is that this is an issue that can be corrected in a future software update, as it does seem to be software related. In the meantime, my AIRAVE will remain unplugged and collecting dust.