I did a little testing, and I found a work-a-round to the lava bug where your music stops working(ex. when in Dralk). Its quick and simple.
Go into your Istaria install folder. Then goto \resources\sound\ambience. In there you will find lava_fire.mp3 and lava_00.wav. Move these 2 files to your desktop(or somewhere for safe keeping[I deleted mine]).
I then took the file fire_small.wav and made 2 copies of it in the above mentioned folder. I renamed one of them to lava_fire.wav and then renamed the other to lava_00.wav.
From here we have to change one small detail in the Sound_Ambience.def file. Open it up with notepad(or your favorite text editor) and goto line 364.. there you should find a section that looks like this
//lava_amb
{
string name = "amb_lava_00"
float overallChance = 100.0
TSample list sampleList =
{
{
string filename = "lava_00.mp3"
bool loop = true
}
}
Change the "lava_00.mp3" to "lava_00.wav".
And Voila, your sound shouldn't cut off after visiting a lava pit.
My theory is the mp3 may not be encoded correcty for the client to understand and there is some buffer error of what not.
Just my guess