Open ear audial distortions are most prominent on DiPT, as I think most would agree. At (for me, though I prefer higher doses than some) 75-125 mg DiPT oral, I experience at peak profoundly nonlinear pitch and timbre distortion on every objective sound. I've also had (very different; more temporally choppy, more like the auditory equivalents of flicker and trails, rather than the auditory equivalents of warping and colour shifting) OEAs on >=25 mg doses of 2C-E oral.
Closed ear audial hallucinations, again, I feel that DiPT guarantees them best, but I've had lush CEAs on LSD and 2C-C too, and had some fairly spectacular ones last night on 15 mg insufflated 4-AcO-DMT. I'd never had them off 4-AcO-DMT before, but then I guess I hadn't laid in silence and attended to the possibility of them until last night. Like CEVs (and, which I think are equivalent, OEVs perceived in essentially blank objective backgrounds such as plain walls or skies), I find CEAs are attentionally modulated and easiest to perceive in silence.
They tend to be quite pure in timbre (although they are often harmonized, when on more intense doses), but with plenty of variation in pitch and in amplitude, with often an amplitude overlay of low frequency flutter, as well as high pitched swoops. They resemble a sort of music, but not the sort of music any conscious human would make, I think.
At their mildest, I find CEAs (on any psychedelic that elicits them) resemble mere tinnitus: a near-constant very high pitched tone (again attentionally modulated, such that it may become obscenely loud if attended to too closely). At their most intense, they are among the richest, most exquisite, enchanting, and bewildering aesthetic forms I have encountered through psychedelics.
For reference, other psychedelics I
don't remember having audials of any sort on include: 2C-T-2, 2C-B, psilocin (and esters) in psilocybe mushrooms, DPT, and 5-MeO-DALT (but this last I've only tried at (as far as I could tell) sub-psychedelic doses).
ETA: Only hallucinated voices on cannabis and other cannabinoids. Same for full on, from nothing, lifelike visual hallucinations (of, say, people; or horses), which I had on many occasions off cannabis when I was younger (and my cannabinoid receptors were presumably in better shape), but never off any serotonergic psychs.