> So, can no one give me any suggestions? Perhaps I can elaborate upon > further testing and attempts to debug this tremendously frustrating problem. > > My softphone (typically IAXComm, but same results connecting via SIP on > Xten Xlite) is installed on a P4 1.6 w/ 256 megs of RAM and an > integrated sound chipset (Intel/AC97). I've had some problems with this > chipset in Linux, and it doesn't support hardware mixing, so I've had to > attempt to get dmix and ALSA running in an acceptable fashion; needless > to say, I still have problems, and I don't know if this is related. > > I can record and playback my own voice and other audio (podcasts, Net > radio, and music) fine with this headset (some cheap, Chinese $15 > headset). However, when it comes to receiving decoded audio on the other > end of a VoIP conversation, it sounds "scratchy," distorted, crackly, > whatever you want to call it. It's not the clarity so much as it is the > other things I just mentioned. It's very hard ot put into words, but I'm > hoping *someone* can associate with my problem. > > To make sure it wasn't my Asterisk box that was mucking things up, I > connected directly with my softphone to my outgoing VoIP terminators, > voipjet and Voxee. Sure enough, it sounded *exactly* the same as it does > going through my * box on the LAN and then out through the public Net to > voipjet and/or Voxee. Thus, I know it is my side of the equation that is > mucking things up, but I cannot for the life of me pinpoint exactly > *WHERE* this is taking place. > > Actually, I also unplugged my headphones and plugged back in the > speakers, and it sounded roughly the same, but it's harder to tell > because they're not surrounding your ears, quality isn't as clear, and > ambient noise can be more easily heard and is distracting. > > I'm thinking, at this point, that it's my sound card that's messing > things up, or its configuration or something. However, can anyone > explain *why* non-VoIP-conversations sound perfect on my speakers and > headset, while VoIP calls sound very bad?
If I were to try to diagnose the above, I'd be using Ethereal to capture the voip packets coming from your itsp's, and analyzing that captured data to look for unusual things. If your itsp connections are sip based, ethereal has a utility to analyze/summarize some of this for you. If those connections are iax based, then you will need to analyze the packets yourself looking for unusual things. Analyzing the packets (either sip or iax) can consume a lot of time, but you really need to ensure those packets are arriving in a consistent manner, timestamps contained within the packets are consecutive and proper, packets are not arriving out of order, etc. At the same time that you're capturing those packets, use the facilities within asterisk to summarize what it thinks is going on (eg, 'iax2 show netstats'), so _that_ data can be correlated to the info derived from the packet captures. If this is a small soho * system, then run ethereal right on the same asterisk system capturing the data as it arrives at the system. Doing so will help identify any issues that you might have involving your local lan, broadband issues, etc, etc. Assuming the problem that you've described is consistent and happens on a regular basis, you don't need to collect and analyze megabytes of packet captures. Just collect a short duration sample that is assured to contain the representative packets associated with the bad audio (maybe five or ten seconds worth). If the analysis does not indicate a problem at that point, then at least you know the problem is internal to asterisk, etc. If you don't feel you have the skills or knowledge to do that analysis, then hire someone that can. Both your original post and the followup post contain a ton of adjectives and adverbs describing a technical problem, but contain little (or no) technical data (such as the results from above or results from various * show commands) that would allow anyone to comment on your problem. So, doubtful anyone is ever going to reply to such postings with anything helpful. _______________________________________________ --Bandwidth and Colocation sponsored by Easynews.com -- Asterisk-Users mailing list [email protected] http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
