Odd audio issue with FT-897D

[n3ntj]

I have a Yaesu FT-897 and I notice that on occassion, while on 10M SSB, the audio level cuts out a little (to approx. 60% of the regular audio level). This audio includes the background atmospheric noise and any radio signal on the freq at the time. I can often 'correct' it by pressing the PTT button, then the atmospheric noise audio level comes back to normal. This doesn't always fix it, though, and sometimes several PTT presses are needed. Sort of an annoying and odd issue. It seems to only happen on 10M. If this issue is happening on 10M and I flip over to 15M or 20M, the atmospheric noise audio level is normal. Has anyone else noticed this issue? If so, anyone know of a fix?

Thanks.
73 de N3NTJ
Matt