Zapateller tones garbled

Newbie here. Searched all over for the answer to this one and could not find it.

I have Asterisk 1.24 running on an XBox with Fedora Core 4. I use a Sipura SPA-3000. This is connected to a Vonage RTP300 ATA. I am using * to mainly address the fact that Vonage is lacking some critical features, e.g. ACR, etc. This setup has been running for several weeks and is working great!!

I recently added Zapateller() to my ACR path in extensions.conf. The problem is that the SITs are somewhat garbled when I test it from another phone. Note that I have many sounds working just fine. I am suspicious that the problem may have to do with no timer. Zapateller() makes its way to ast_settimeout() in channel.c which has an “ifdef ZAPTEL_OPTIMIZATIONS” clause. I do NOT have zaptel compiled or installed on this setup. I have started looking at what is involved to get ‘ztdummy’ installed and wanted to find out if this will likely fix my problem or there is another problem going on. My only other guess would be that the Sipura ATA or my RTP300 (Vonage ATA) is doing some sort of DTMF mangling.

Thanks in advance for any info.

I created a gsm file that has the three tones that make up the SIT (950, 1400 and 1800Hz, 330ms ea). When I use this instead of Zapateller I am still getting the same garbling so it must be a DTMF problem or some such. Need to keep investigating.

Pretty sure I figured it out. Vonage lets you select which codec is used in the Vonage ATA via the “Bandwidth Saver” feature. I had the Normal setting in place (G.729 codec). I jacked it up to the Highest Quality setting (G.711) and the SIT tones come through loud and clear. I also switched back to using Zapateller to generate the tones and even though I have no zaptel-based timer (not even ztdummy or zaprtc) the tones sound fine.