With the dialog and acc modules configured to generate CDRs to syslog, sometimes a CDR is not generated when a call ends. It appears that this is because some callers are closing the websocket just after sending the BYE. That means that when the 200 response to the BYE arrives it can't be relayed as the websocket has closed. It does seem to be timing related.

We use the websocket close event to shorten the dialog timeout to 1 second.

We also don't get a CDR if we close the websocket while a call is active. The dialog times out and sends a BYE to the callee (it fails to send to the caller, not because the websocket is closed but because the *.invalid contact address can't be resolved!) and then destroys the dialog.

[kamailio.log](https://github.com/kamailio/kamailio/files/5702715/kamailio.log)

[kamailio-sipdump-2020-12-16--11-13-52.data.log](https://github.com/kamailio/kamailio/files/5702719/kamailio-sipdump-2020-12-...)

* **Kamailio Version** - output of `kamailio -v` version: kamailio 5.3.6 (x86_64/linux) fb26c8 flags: USE_TCP, USE_TLS, USE_SCTP, TLS_HOOKS, USE_RAW_SOCKS, DISABLE_NAGLE, USE_MCAST, DNS_IP_HACK, SHM_MMAP, PKG_MALLOC, Q_MALLOC, F_MALLOC, TLSF_MALLOC, DBG_SR_MEMORY, USE_FUTEX, FAST_LOCK-ADAPTIVE_WAIT, USE_DNS_CACHE, USE_DNS_FAILOVER, USE_NAPTR, USE_DST_BLACKLIST, HAVE_RESOLV_RES ADAPTIVE_WAIT_LOOPS 1024, MAX_RECV_BUFFER_SIZE 262144, MAX_URI_SIZE 1024, BUF_SIZE 65535, DEFAULT PKG_SIZE 8MB poll method support: poll, epoll_lt, epoll_et, sigio_rt, select. id: fb26c8 compiled on 11:51:56 Nov 17 2020 with gcc 4.8.5

* **Operating System**:

Linux ip-172-30-0-66 4.14.114-83.126.amzn1.x86_64 #1 SMP Tue May 7 02:26:58 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux